Holley Efi Unterminated main harness building from start to finish.

hey guys today we're gonna go over how to build your own unterminated harness from scratch and and get decent results out of it so the first thing I wanted to show you is that when you pull the tape off of this it's enormous right so this thing's like 15 or 20 feet long so this can be intimidating in its own you open up the box and you go man what the heck is all this stuff so so I'm going to kind of go over how I do things this this car that I'm working on now is a turbo alcohol car we're using a Dominator so the first thing that I'm going to be doing is I'm going to be removing out of this what we don't need okay so you've got a that you want to eliminate as much as you can to begin with so you're not working around stuff that you don't need right so we're going to just go over a couple things here first and the unterminated harnesses these are your cam and crank leads okay so they're already terminated for 12 volt here on B 20 and then they combine 12 volt here and then you've got your signals and then you've got your since your your cam and crank grounds here okay so these shielded cables are going to be cam and crank what you'll have to do is a you know segregate the two of them and figure out your length so we're going to go over lengths in a minute this other big shielded cable is your wideband o2 sensor typically the first thing once I have everything out of this harness that I don't need the first thing that I trim to length is the wideband o2 sensor in the cam and crank because they're big they're bulky and you can get them up out of the way show them over on the bench with this car I'm going to be removing all of the inputs and outputs on the main engine harness because we're not going to be using them because I'm using them in the Dominator so I have to try to keep when I built a car or build a harness and I wire a car I like the engine harness right J 1 a and J 1 B to run the engine and that's it I you know this is when you're using the Dominator if you have an HP you don't have an option but if you're using a Dominator I like to disregard if you can the four inputs and outputs that are in the main engine harness so that you don't have any tie-ins with like a dome pressure sensor or anything because the the number one thing we got to do is is keep the car running right so all the extra auxilary stuff I like to put here so if you have you know one of your other one of your other connectors but uh I like to always keep the engine harness as minimal as possible so that there's less likely a bad sensor to cause a problem and have the thing not run right the next thing I'm going to do here is I'm going to remove the idle air control the NOC and all that kind of stuff because we're not going to use it on this thing and then finally one of the one of the biggest problems to actually get a clean good-looking installation is people run into an issue with you know what they're going to do with this relay fuse you're loose you know switched power and ground so what I want to do is I want to show you kind of how I go about this so this car has a single set of billet atomizer 850 pound per hour injectors they're big and it's got smart coils on it and you know we want to supply a good bit of power to them so what I do is I actually got this this this factory relay and fuse out of this harness okay and if you're gonna do this I suggest picking up the flying lead harness the only difference between the flying lead harness and the unterminated main harness is that it does not come with this and it does not come with all of your connectors that you'll need I feel like me and you've got a stockpile of all this stuff then you can get away with not using the interpreted rain harness if you don't have all this stuff I always recommend buying the unterminated main harness and then you know cut to fit so once you've had you know what what I'm gonna do here is I'm going to pause the video I'm gonna gut what I don't need out of this harness and we're going to see how much smaller it gets then I'm going to get into measuring what you want to do or you know where it's got to go and how to measure for it properly and then we'll get into actually building it so give me a few I'm gonna pull what we don't need out of this and I'll be right back all right so we've gutted what we don't need out of our main unterminated engine harness okay so we got some you know idle air control stuff so our outputs or inputs we've got the points wire the tach output so so again this is in a Dominator application this is how I do it and of course you could leave your inputs and outputs in and you can terminate them however you want and I'll show you how to terminate your inputs and outputs here shortly when we get into the actual building of this harness but for this application for what I'm working on and for the way I typically do it a Dominator has got so many inputs and outputs that I I don't like to use the first four that come in J 1 and J 1 B so those are all removed and now this gets a lot less intimidating okay so this is really all that's needed to run the engine it's not that much here now granted it's still too long but this is a lot easier to deal with so I removed a couple other things and like I said about this this relay that's in the harness and and we're gonna go into that right now so this wire here is it comes from j1 pin to j1 a pin to okay and we're gonna go over here we're gonna look at the diagram I got a blow up version of it but if you see it says j1 a - it's a red wire it's a fuel pump relay out okay so what that does is it sends a signal a 12 volt signal out to turn on a relay now hopefully you guys understand how it really works if not we're going to give you a little quick quick education on it okay so this is the relay that's in the harness typically you have this black wire that's loose and this red wire that's loose and then you've got these two over here we're going it to that so this is the first wire we just talked about okay j1 a 2 this is the 12 volt signal out of the ECU to turn the relay on alright so it turns his relay on when it sees our p.m. so what it does is it it's gonna power the relay this goes to a good chassis ground or battery ground either one because this is a very low current lead these two leads are very low current okay so the purpose of a relay is to take your power right to be able to supply more amperage capacity from a smaller device all right and so you got power in so typically this would hook up to your your battery right or somewhere where you're pulling a good solid 12 volt from and then this would go to your chassis ground this goes to j1 a - okay which is this this is your coil for the relay these right here so when you give this 12 volt and you give this ground it basically allows power to pass through this into these outputs right so you look at this is the input side of the relay this is the output side of the real life okay there's a diagram on a relay there's a billion in one videos out there on how to read a 12-volt relay them it's very simple but for the relay that's in the main engine harness right there it's all based off a pin location and if you slide this out you'll see kinda hard to see but you can see the it's stamped in there down in here so show you guys it's got a relay that's how that works now the reason I got this out of this harness is because we've got smart coils in this car that need a good 12 volt power and we've got some big injectors that need a decent supply for 12-volt power with the factory setup what this is is this this red wire that's the output and notice the bottom here this is literally just this is two wires terminated to the same pin okay this is a typical you know 5-pin 40 amp relay from Tyco boss whoever and this is that they rate them for 40 amps okay which means this wire has to be big enough to supply 40 acts and then this side shouldn't draw more than 40 amps well for for for what I'm doing with this car and again you don't have to do this but for what I'm doing with this car I like to go to a little bit bigger better more robust relay setup for this right so I got these out of harness now these may look familiar to some of you okay so this red wire would typically power your injectors and then this green wire is supposed to trip a second relay to turn on your fuel pump okay so what I like to use in this application is I take all of this and I remove it from the harness okay and just remember j1a to is your 12 volt we're gonna use j1 a - okay and I switch over to something like this right so an MSD this is for relays in one okay so it's kind of more amperage capacity and we've got some more outputs a little bit more versatile and we'll be able to do a little bit more with it and it's all in one nice sealed unit right it's all solid-state got some indicator lights whole nine yards I've made another video on this already there's a bunch of videos on this floating around how to hook this up but it's very simple alright so what we're gonna do with this car is this this terminal here that's indicated with a G okay so that's ground so this entire bus down here is all ground triggers okay but no matter what they say thermal needs to go to a ground so think about it this way this relay needed a ground this relay still needs a ground no matter what okay now this relay instead of being fed by this single 12 gauge power wire I'm gonna feed this with six or eight gauge okay now you could feed it with four gauge and now you've got four outputs right so it's basically four of these and one and then we have four ways to trigger it okay so all four right so first output first trigger whether it be ground or power so what we'll do with this situation is I'm gonna take a wire and go from j1a to right where this was where this was plugged in I'm gonna run a wire to as many of these inputs as I need on this so I want the coils to be energized and the injectors to be energized when the engine Cesar when the ECU sees engine rpm okay so again G ground the chassis ground and then all four of these are gonna get powered from j1 a - all right so now we have the capacity to feed the big set of injectors a bunch of amperage capacity to the to the coils or oversize and things to make it you know problem-free this car has got smart coils it's on alcohol and it's probably going to make some run the neighborhood of three thousand eight horsepower so we don't want to rely upon just this to power the whole thing all right so so I just walk over to one of these that's the reason why I remove this from from the from the engine harness okay so if you've got a you know maybe you got a c10 with a stock LS in it use this you don't need to worry about it all right but for this application I like to be able to provide a little bit more amperage capacity to the big current drawing devices right like the smart clothes I'm like a big injector and whatnot so that's why this is removed so J 1 a 2 is out of this harness right now but it needs to go back in now I know this and if you're watching this you should know this as well ok now we're going to discuss some of the other loose leads that are hanging out of this so this one j-1 a10 this is your 12-volt switched wire okay and the reason this is called up is because I know on this application the source for this is only about here alright so I just call this up to show you so j18 n this is what actually turns on the ECU alright so you've got your your main power and ground that's gonna go back to your battery but you still need to turn it on so this seems to be a problem for a lot of people and they hook this up to a lead that loses power when cranking if it loses power when cranking guess what happens to the ECU and you're cranking it turns off okay it's not hard to understand this has to have power while cranking well in the on position okay this has to have power alright it's gonna turn off alright so I get this question a lot man I just installed my stuff blah blah blah if you know it everything reads right I hit the key and then the - shuts off and then they won't start okay that's because this water probably loses power alright this one this one's pretty important here okay I'll write this down j1 8:10 this one needs power while cranking - okay so when you put it in accessory if you're using a key or wok cranking if you have a switch panel in the car run this to one of the outputs off of the relay board for the switch panel alright if you've got a big relay board in the car maybe got eight relays or whatnot what you can do is you can run this to one of your inputs for your relay board and then you can run a1 a2 to an input for another relay to power your injectors and your coils or multiple relays to power your injectors and coils so you have a nice clean you know two wires coming out of this to hit your relay board input side so again I can't stress enough how many people hook this thing up to when they turn the key that lead loses 12 volt and then they blame Holly and they say oh man this thing's junk blah blah blah you have to understand that this has to have power while cranking okay how's that firewall cracking just say it one more time power wall cranking it's not there it's no working alright next loose lead out of here it's CANbus okay so can bus is how your dash eg tease a bunch of other stuff communicates with the ECU to wires I like to leave this loose okay out of this bundle well I didn't I leave this in a bundle up to maybe 12 inches away from the ECU and then it'll break out in some applications and if you're savvy enough you'll understand that one there's a reason why this is twisted and two you can replace this wire with something longer if you'd like okay so if you pan over here this is wire that would just remove from do you see you know it's even got the terminals on it right so I understand that it's orange and arms with a black stripe from the factory but if you're keen and bustle lead is a little short you can make a new one with wire okay and you can run it to where you need to run it so you plug in your devices so let's go throw that one out there as well if you can sense a little bit of my frustrations because I get a lot of the same questions over and over and over again so I'm trying to really harp on this so that y'all can understand how you can make things work and look nicer and be better and perform better and last longer if you just take a little bit of time now most people watching this are building a race car race truck whatever it may be so racing is awesome do it all time love it I do not race through this job okay so that's the other thing that I'm gonna harp on here if you look at this what you have leads out what I've got laid out here right and you think man I should be able to get this done in like two or three hours put it all back in the box and return it by a plug and play harness you're not going to get it done in two hours okay which is not going to happen so need to dedicate some time to this I have installed I've wired and installed this is car number 63 for Holley EFI okay so they do them all from scratch this is card number 63 I am about as proficient at this it gets grant that I gotta take some time out to make these videos but I'm about as proficient at doing this job as it gets I'm sure there's somebody else out there that's a little bit better than me a little bit faster or whatever it is but I'm about as proficient as it gets I do not set aside two hours to do this job this is a all weekend long job for most of you okay to build just this main engine harness okay and the only way that you should be getting to build this main engine harness we're gonna look at the car here in a second but this is your last thing that you do and I don't just say this I really mean this I wire cars in layers is the easiest way to explain it okay and I've done another video on that you can watch it you should watch it you should also subscribe so that you know I don't have to go over this all the time and you can just watch my videos and everybody learn something and it'd be great but this is the last step okay so we're look at the computer here for a second right and and and I'm going to show you this is the car that I'm wiring right and I'm gonna show you J 4 J 3 okay view outputs all this stuff's done in the car all of this is already done in the car alright we're gonna look at it in a second I've already got my relay is mounted for where I want them to be so that I can take measurements of where it's all supposed to land all this stuff is already done alright if you notice there's nothing here in j1 okay nothing here in j1 be alright the plan is to build this engine harness dead last a lot of people get this box they open it up in the Jojo of the unit circus pool with a pretty new pet and they want to put together their engine harness because they think that that's the most important thing to do everything leading up to this is the most important thing to do this by the time you get to this step this should be easy okay you should be watching this video go on Devin you're an idiot this is easy stop hyping it up the reason I'm hyping it up is because y'all gonna ask the same questions so we're gonna go look at the car and I'll show you a couple things under the hood before we get to the measurement part of what we have to next okay so we've got this thing stripped we've got everything out of it that we don't need now we need to start measuring distances and as you can tell you don't want to coil up twenty feet of this and shove it up underneath the dash like some people all right so we're gonna cut this stuff to length we're gonna start terminating some stuff but the first thing we need to do is we need to figure out how long everything is going to be so let's go over to the car all right sort of the hood to show you some stuff here so before you get to making this engine harness all right all of this stuff should be mounted all right so we're reusing some other sensors from the previous EFI system that he had but this is going to be his fuel pressure sensor this is mounted it's in its location all right this is the coolant temp sensor it's mounted in the location if you notice there's already I already built a milspec injector harness for this car all right so it's in its location the Kreg sensor is in its location all right the cool packs these are some provided cool pack harnesses I don't I'm going to use them but it's in the location as to where they're going to be so the path the cool packs are already mounted okay all the stuffs already mounted where it's going to stay in the car the reason why this is important if you look over here I'm gonna show you the rest of stuff right so we got a map sensor we're gonna intake air temp sensor this is the plug for the injector harness all right this is the plug for the cam sink the reason that this stuff is already mounted is because how else are you going to measure for it all right I've gotten questions from people that say oh I've got my my engine harness buh-bah and then you know I bought this pre-made and it doesn't line up to where I wanted to put the plug well whose fault is that you should have bought the injector harness and plugged it in or built the injector harness plugged it in and then said hey this is where it's got to go all right so get all this stuff mounted where it belongs all right if it would go over the other side of the car you see that uh do two sensor right it comes with a really long lead you know when you buy it onto sensor right so because our long lead but it's already ran to where it's going to be all right so this o2 sensor this is where this o2 sensor is going to be in this car and it's going to run to here so when it comes time to measure we know that the plug has got to land here all right the plug doesn't have to land here otherwise we've got two and a half foot of quarter we're going to coil up and do what with wrapping around the waste gate so it burns that you complain now mount everything right mounting everything is like one of the most important things to do and if you want a nice clean looking you know well-designed harness right you need to know these lengths these lengths aren't just arbitrary or I will add five inches here to be fine because then when you're done you look at it and go oh this looks like crap I screwed up I should have done this session of than that the purpose of this video is if you're going to build your own engine harness if you're gonna wire your own car just take your time and do it and it's also the other part of this this video the other purpose of this video is that I wire a lot of cars okay so if you if you watch this and you say man this is over my head I don't want to deal with this or you know whatever it may be hit me up and maybe I can get you on my schedule I'm booked for a while I stayed booked pretty much all the time but you know maybe we could work something out but either way the focus of this is to get you to wire your own car and to be happy with it so the next thing you got to do before you your you're about to about to build your engine harness is you need to figure out where everything under the hood is gonna come through the firewall so on this car like I said I'm harping back on this everything's gonna be mounted thing but there's a grommet already in the firewall alright so that's where I put a grommet in the firewall and again there's some stuff underneath the hood that I've already wired but it doesn't have anything to do with the engine harness right so there's a dome pressure sensor down there like buried down there there's some you know some auxiliary stuff that we're not going to be I'm not going to get into with this but it's already through a grommet down in the bottom of the firewall out of tucked out of the way nothing else is coming through this hole except for the engine harness all right so the goal here is to mount everything you strip the harness down you've mounted everything you want to be sitting in this position and say okay now I am ready to start building my engine harness all right so the next thing we're gonna have to do is this might be a little hard to see going over the top yeah here we go okay so yeah alright so so the ECU is mounted okay like I said J 3 and J 4 they're already done all right so J 3 J 4 is already done so when we're looking at this car okay your car right we know that these are the plugs that the the main harness is going to come out of right so so kind of get an idea of how you want this to flow because we've got a 20 foot of wire right so I don't want this to come out and do a hard 90 this way and then cram up in there and make a mess right so maybe we want to go out here along this bar here then up kind of hard to see and and we're going to come along this bar here then we're going to follow this bar up here maybe drop some some P clamps here hold it tight and come through the hole or maybe we want to come up here here and then across the dash bar up here and then go up through the hole up in here ok a little hard to see but whatever so lay it out how you want to lay it out right and get you get a good solid thought process on how you want this thing to flow through through the car okay a lot of you guys are probably looking at this car going oh man this thing looks like a cakewalk like that you know or nightmare because look at all this stuff everywhere these are easy you guys with a street car or a street truck with a dash and AC and whatnot this is even more important for you than it is for me because if you can't focus on the fact that this wire has to come through here and go out this way and then you forget my a/c systems in there well it may suck but you have to pull you may have to pull out AC system out to be able to route things where you want but you better Mach it back up so that your wiring harness doesn't run through an area that your AC system is going to cover alright so you know just keep just keep it in mind so the next thing we're going to do we know we got everything mounted okay we know we got everything where we want it to be forget everything gutted out of the engine harness the unterminated engine harness we know where it's all going to go okay so we got all that nailed down so now it's time to start cutting well before you start cutting might I suggest Mushu she's sleeping my girlfriend's got the video camera she's obsessed with the dog so deal with it might I suggest $3.00 at Walmart or wherever these little things okay so all this is is a fabric tape measure okay it's what your your mother or grandmother's probably got one if she you know knits and sews and whatnot these are great the reason these are great is because you look wire bends right see that okay this thing bends right let me show you something here all right everybody's got to take one of these in their in their drawer right in their toolbox alright look what this does that's stupid this is dumb to try to get some measurements of something that's going to bend right so don't use it this is dumb I'll use this okay dumb right agreed smart this kind of looks like wire all right we're gonna yeah flex code is exactly yeah hey look at me okay anyway so we're going to start measuring right so here's the next thing you want to do this is paper okay a lot of you younger guys probably don't even know what this is but this is paper has got lines on it all right and then you use a pen all right okay you can't ask Siri to do this for you but you use a pen all right they sing if you could tell this is not my handwriting okay anyway see this right so this pen look at that it makes marks on the paper right so you do hopefully our education system hasn't failed us completely yet you're right to hound so much I'm just busting your balls you know write down what you have going through this engine harness okay so first thing we got to see you to firewall all right so this measurement is gonna be from your ECU right plugs at your ECU okay to the hole that's in the firewall all right now something I'm going to tell you right now if you don't zip tie this thing to the bar or to wherever you plan on running it these will slide through your fingers so the old adage is measure twice cut once that stands true for this application as well so measure twice cut once I'm also going to tell you that the way I do this you're going to mock this up more than one time so if our ECU to firewall measurement let's just say it's 50 inches I'm gonna write down 55 inches I'm gonna give it 10 percent okay so I like to add 10 percent to my measurements and the reason being the reason I about 10 percent to my measurements is because I twist most of these and you're twisting wire I always like to be a little bit longer than I do shorter because you can always cut more wire off and I remember the whole point of this is it's unterminated we're going to terminate this so once we have this measurement ECU to firewall the rest of these measurements are going to be easier from firewall you all of these items okay then I take a measurement for switched power and this measurement let's just uh I'm just these are arbitrary this isn't accurate from this car but let's just say it's 22 inches okay but what we're gonna do is we're gonna we're going to write down a breakout right and it's gonna say 14 inches breakout what that means is you're gonna hear we say this a couple more times breakout right what that means is that this this that this number is inaccurate but this number is going to come 14 inches right we're gonna come down this harness 14 inches right and that wire is gonna lay here until 14 inches and then that wire is going to break out of that loom the rest of these the rest of this loom is going to continue on okay so it's going to be so I like to write down this is its overall length but this is the breakout because remember we're gonna have this whole loom follow a nice lead into the firewall pass through all right and then the other thing is we're gonna have a breakout for injector power and coil power so you're gonna want to run your cool power and your injector power in this harness when it passes through the firewall you don't want these you don't want you know - 10 gauge 12 beats whatever it is wire hanging out outside of your loom outside of your harness it's actually going into the engine bay you want it to look nice right so that's the whole purpose of using it on turnaround harness that's the whole purpose of taking your time and doing it right so what you want to do is you want to figure out where your break out or you can call it break in for inject their power and clueless okay so let's just say we're gonna be up here around here this is what we're going to break in our our power for our injectors and our coils well if we're breaking out here or we're breaking in for injector and coal power here what else has to come here all right what has to come here we're gonna guess that this is sitting there we're gonna have power coming here and here it's going to come up through here and into the harness and follow the rest of stuff out well what else has to come in here on this side what has to come here on this side is our wire for j1a - so that's where we're gonna have to take a wire we're gonna crimp an end on it or we use one of these right we're gonna terminate here and a - we're gonna run wherever we think it's gonna break out at right right here and then you're gonna break out right so this is j1 a - coming up here and we're gonna hit our triggers for the relay okay and then this side is going to company at least four right are however many outputs you're gonna use it's going to come here and go this direction with you know the rest of it and then this is going to be your firewall area here right so nice and smooth come through here break out go here and then break in from injector and cool power in here to go out through the engine bay so what I'm going to do now is I'm gonna take some measurements and and we're going to start I'm going to show you how to you know cut this down how to do your breakouts and how to do your tie-ins for your five volt bed and sensor ground so I'm gonna go grab some measurements and we'll be back in a minute all right so we got everything cut the lengths I've got some stuff kind of laid out I'm gonna go over before you go thinking you should start putting some loom over this or you know covering it and heat shrink or whatever you're going to do all right so everything's cut the length the first bundle of wires I want to look at here is our sensors okay so in this we've got we've got throttle position we've got intake air temp map sensor I just happen to remember the colors fuel pressure coolant temp oil pressure all those sensors need either both sensor five volt and sensor ground or the temp sensors just need sensor ground so if you look if you look close you can see a silver mark on them right here all right so I wrote a draw a draw on everything with a silver marker it's really easy to see there and that is my guesstimate of about where the firewalls gonna be right so I took my measurement right here ECU to firewall it's 55 inches so my example from earlier I actually happened to be correct and I string out fifty five inches from the plug to a mark and then I mark it at 55 inches right so now if you look at these measurements here's what we talked about 55 inches to the firewall and then this is from the firewall to here to all these different things right and then over here is the total all right so you want to know that you've got from the firewall you know 15 inches to the injector plug plus 55 at 70 all right it's a simple math so you know hopefully you don't do the Common Core math but 70 you just started adding them up this it should be your total so your total overall length from ECU to each individual item will be here but this is from firewall to each individual thing right so if we've got 55 inches from ECU to firewall all right there's our mark right you can see it right there we need to break these out and start following leads and making either these two wire or three wire bundles teach one of these sensors right so I always cut them short and you know she's not sure I cut them shorter than where the they break through the firewall because wherever it breaks through the firewall and this car goes on alcohol everything in and the engine bay is gonna be covered in dr 25 so i don't want a junction out past the firewall i want it before the firewall now if you're using a bulkhead connector this is where you you you know this is where you your measurement would go ECU to firewall you'd cut it at 55 inches and then you'd make a lead from the other end of the bulkhead connector out to all of these different devices if you're good you can do your junctions in the back shelf or the bulkhead connector with some stub splices and whatnot if you're to that point you probably aren't even watching this video anyway because you already know what you need to do so I'm gonna focus on not using a bulkhead connector because with this car we're not using a bulkhead connector and we're just using a grommet and it's going to come through like every other car out there so we need to be able to break these out and I like to break them out before we go to the through the firewall so I just cut them short I'm actually going to cut them back a little bit shorter and we'll be using some stub splices or a step-down buck connector and we're going to you know cut one end terminate it and then on the other end will have either five or seven right so there's one two three four five six sorry there's six sensors here right and only four of them need five volt right but all six of them need sensor ground so sensor ground is going to break off into six different leads and then this is going to their five volts a long going to break the four different leads right so all of your your five vault sensors are your pressure transducers and your throttle position sensor your map sensor those all need five volt and sensor ground your your thermistors your temp sensors right intake air temp coolant temp and blue right here in taking our temp they're two wire they only get a sensor ground so that's the first thing I want to point out before you start terminating stuff thinking you know put it all in a bundle you're gonna have to make your breakouts and I do these breakouts before I do anything else all right so let's put these out of the way and let's start talking about here's your cam and crank right so we've distinguished this shorter lead was our cam this is our crank they're two lengths right so right here cam will end up being 65 inches crank wound up being 95 inches right and again these are gonna be long I went a little long with them all one for the educational purposes of this video too because it's a heck of a lot easier to cut this stuff back than it is to try to figure out how to make it longer okay you're given a whole bunch of water when you buy one of these on terminated harnesses use it so and with that said let's set having a whole bunch of wire alright I left this out this is what I cut off of the sensor 5 volt sensor ground okay if you don't have any other wire laying around you can make your branch point a little further up the line but I always like to do it inside of the car alright so we've got what car cam and crank your o2 sensor is just one shielded cable so let's cut and that's going to wind up be in the core of our bundle so there's really nothing to do with this except for once we get it to length we're going to we're going to terminate it you know strip it back and terminate I'm going to show you that as well alright the next thing we need to talk about I use are you zip ties just to segregate this stuff for purposes showing you these are all of our injectors okay so we know our injector plug was roughly 70 inches total from the ECU so here's all of our injectors alright so I keep them separated and if you notice here's your mark that's to roughly where the firewall is going to be right you're 55 inches and remember we're gonna have to put power in this so when we put the power for the injectors in the coils in this bundle we're actually going to end up working backwards and I'm going to show you that but I'm just I'm explaining why you don't want to just hop in and start looming this thing up and say oh we're good to go so here's our injectors will keep them segregated now we've got coils and this seems to be a pretty common problem amongst you guys especially the ones that are building their own engine harnesses okay so this is our two different banks of coils if you look you'll notice that one bank is a little bit longer than the other because it's got to go to the other side of the engine the other side of the engine so and if you remember earlier I said that I wanted to leave these alone well they're a little long but notice there's four wires per side one for each coil there's another wire that has to go into each one of these bundles and that's this right here it's black with yellow okay so this is what they call it this this comes from j1 B 14 okay and they call this est ground all right so this is the ground that goes back to the ECU from the coil harness all right well this needs to go to all eight coils so notice again I've cut this one short here's all eight of our coils right there's our mark for where we think the firewall is about to be and notice I'm on the inside of that so you want to be on the inside you know you make your Union because when this comes out of the firewall it's going to do this right it's going to go one side is going to go to one direction once I was going to go the other direction well you don't want to make this Junction way up here and then have to hell what do I do now I'm going to come back and go over there so do it on the inside of the firewall and again I've got a bunch extra wire you cut off so you can make your branch and go out to both sides of the engine bay so what I'm going to do here is I'm going to I'm gonna do all my sensors first right and I'm gonna find my branch points where I want to make my Brandt my breakouts because I'm actually gonna wind up bringing them back a little bit further away from the firewall I like to do it on a straight run along a bar just so it's a little bit supported I made another video on how to do your branch outs but but use a good adhesive lined heat shrink over top of a good quality step-down but connect their stub splice or or you know all uninsulated don't solder it doesn't last don't solder just don't do it use a good quality step-down butt connector or a uninsulated butt connector or a stub splice they worked really well and cover it with a good quality dual wall adhesive lined heat shrink to seal it off so that's it I'm going to work on getting all this stuff to do what we needed to do and once I've got a reasonably long run I'm going to show you you know how to break out for your injector and coil power how to do your breakout for your switch to power and whatnot and you know and then how to do your branch outs for your your coils and whatnot so give me a few and let me get this whipped up alright so we've got our our main loom we're already cut or cut the length so all based off of our measurements here so we took all of our measurements we cut everything the lengths we've got a couple things going on here so I want to show you what we were talking about with breaking out you know different things or answer here's where the can bus breaks out there's a switch power breaks out so here's your this is our injectors right this is gonna get filled with more wire but what happens here is is you've got power that's going to go to our relay block and then here's our wire from A to A one A two the one that's going to trigger the relay block to power up our our objectives McCool's here's our junction that we made for the coils the EST ground that I was telling you about before so we've got a junction here it's covered in you know adhesive lined heat shrink and it's two different lengths right so again here's all of our you know here's all of our passenger side coils with the EST ground here's our driver side coils with the EST ground so notice where this where this junction is we still have our mark where our firewall is so all this is still inside of the car alright so what I'm going to do is I'm going to run I'm gonna loop you know I'm going to wall twist these I'm not gonna twisting in the video but uh what I'm gonna do is I'm gonna layer these over here I'm going to follow up with the power wires for the coils all right and they're going to come out in the same breakout point so they can hit that same relay block so I've got two four four injectors and we're gonna have to fork oil and all that stuff's going to come together through here you'll have your power wires with your with your coils it's going to follow the leads to length so it'll plug right into your big wire well it'll be your big wire coil harness and then the last thing we got left to do here is 5 volt and sensor ground distribution so again here's the firewall this is this is a rough guesstimate as to where I'm going to tie the minute before I exit the firewall because the firewall at the firewall all this stuff has to go all different directions so I don't want to have a heavy trunk of wire I kind of want this whole bundle of wire to come through the firewall in one piece because it's going to have to start breaking off of going different directions so what I'm going to do is I'll have all of this stuff done in a minute here when after I do it all you know I'll show you on the video I'm going to start breaking out two different leads prior to this mark of the firewall so that's why we're doing five volt sensor ground that's why we're doing our split for our coils this is why we're doing our powering for the for the injectors all prior to the firewall so that when our five volt and sensor ground split happens we're gonna have each one of these that's a pressure transducer is gonna have Bobby back here before we hit the firewall we're gonna have three leads you know an orange a black and a purple going out to each each sensor right so we'll have you know orange black and green to go to TPS but I like to do the breakouts before exiting the firewall like I've said over and over and over again but uh I wanted to stop doing what I was doing and show you kind of where I'm at this is uh so I've already I've also already tested this too for fitment in the car right so once I have up to the firewall and I have leads coming out for my all my individual sensors what I'll do is I'm going to mock this up in the car I'll use some some P clamps and some Cliquot hose to hold it in place so that I can remove it and I'll get a more accurate measurement to each individual sensor and you know the cam and the crank and the o2 sensor because some of this stuff is still going to be long that's the whole purpose is to be able to continue to cut it down until you get it to the right right length but before i loo mol this past the firewall I'll mock it up in the car and I'll show you when it's mocked up in the car after I've got all these five volts sensor ground breakouts done and the power ran for the coils as well inside of this so I just want to give you a quick kind of a rundown on how we're going about this still looks kind of like a mess but it's slowly coming together and by the time it's all said and done we'll have a nice clean you know streamlined thin engine artist look here's our whole engine harness I've got it in three quarter inch ray cam gear 25 heat shrink caliper we're using txl wire you know it's not really but we're we're six six ten so for our whole main engine horse it's you know it's your o2 sensor that's your cam at your crank fits everything the reason why you take care to do this type of stuff and keep it nice and tight granted it'd be a lot smaller if I was using all tefzel wire and I built this from scratch but by using by keeping everything a little tight nice it increases flexibility right and Bend radius and whatnot but it also has a lot of smaller footprint in the car so it's easier to identify it's easier to pull in and out if you have to kind of take care and you know move slow and measure twice and cut once so let me do these do what I got to do here and I'll get some leads ran out and next part of this video I'll show you you know kind of how it's all broke out and whatnot lain up in the car so give me a minute all right so we've got the harness you know together mocked up so we're coming you know here's our ECU we're coming out of the ECU got it sneaked up underneath this bar and it's kind of hard to see but I got it hidden up in here we've got a break out here for our switch technician like we talked about before we've got a break out here we've got we've got our coil power we've got our injector power and then we got our switched output 12 volt right here okay it's going to go to a relay over here our relay board over here and then we can bus brakes out way back here it's kind of hard to see but I got a hidden way back here obviously the windshields out of this car so it makes a little bit easier to show you and it's going to go through here and I just got a tip tied to hold it in place so that when we work up underneath the hood we've got a good idea as to where we want to want it to land before I cut this zip tie just a you know a tip for you because when you when you pull this out you're probably gonna have you know an hour or two maybe three whatever to work on the rest of the harness you have to finish so what I like to do is I take a piece of tape I stick it to the bar and I take a piece of tape and I stick it to this heat shrink right to our loom and that way when I want to reroute this we know this is where it was intended to land right so you know that you know the tape is supposed to line up here to here right or make a mark or something here here but I don't like to make marks on people's stuff so you know I use it I use a piece of tape so it's easy to remove but anyway so notice it's coming through there but it's not loomed right I remember before I stated that I wanted to be able to come through individually through that hole you know each lead individually so that it can make some some turns when it goes through the hole so we're looking under here under the hood alright and so here we are we're coming through on the on the engine side right so like I told you we've got quite a few different directions that we have to go when it when it exits right so having a big section of you know loomed altogether right here the you know would put our break point out here we wind up having to do 180 to come back down here want you to go back down there so I like to come through the firewall in separate you know separate pieces right separate sections so if you look I've already done this but this is like I said I was going to combine all my my five volt and sensor ground right so all my leads are already done and again this is just mock-up stage right so we've got our cam sensor and I with these cam sensors I like to be able to leave a little bit of slack here and I like to put the the plug kind of in an area where you know remember there's the other half of this plug you don't want this plug to sit here like this the wire to come up and I'd have to do a hard 90 so I like to give it a little bit of room so so here's our cam sensor lead right and of course it's gonna get labeled and everything before you know it's all finished but there's our cam sensor lead and when I build these harnesses I like to I like to have them yes if you look here like this this bundle here is all gonna go in that same direction instead of coming out going this way coming out going this way a little bit coming out going that way then that way like that won't come out together right so what I'm gonna end up doing is I'll use some zip ties it's use a little couple little zip ties and I'll bundle all these together to about here probably just so that this is nice and clean along the firewall and it can dip down here like this and you don't have stuff that you know falls inside of it and then I'll loop all this stuff together and then same thing with this direction here right so we have we've got a throttle position right here we've got a fuel pressure and then we got a coolant temp and then we got crank signal so all these are going to come together along here while the valve cover and throttle positions here right so all what I'll do is I'll wind up looming these all together to about here so that it's just one piece you know going this way and then we can have breakouts to go to wherever we need to go same thing with back here so if this has loomed all together to here then you know then we could break out we can go you know we're gonna go up and around we're gonna go to the map sensor we're gonna go to the intake air temp sensor up here and then we're gonna have our injector plug right here so that's gonna lay down in here like this and and again we're gonna have that Bend radius that I was talking about you know so so you don't have a hard 90 going into it so it's gonna come around here plug in right there and then this stuff's gonna go that direction because our oil pressure sensors down there the o2 sensors over there and the other cools are over there so what your next step here is is um you bust out the little zip ties and you start tying all the stuff together where you want and you I like to use a little marker and mark where you want all this stuff loomed together too right because you're not gonna do it here in the car you're gonna do it over on the bench so I'm gonna loom like I said we're gonna learn this stuff up to here and then we'll do we'll do two leads you know together to go over here and it's gonna hit over here it's gonna cool a temp right and then your fuel pressure here so I'll wind up using a 90 degree boot here so this will come over real nice lay in here like this you probably asked him why I'm not running it up underneath the intake it runs stuff up underneath the intakes nice until you got to pull the intake and then it sucks because you have to wade your hand in there and on these single planes it's kind of its kind of tough the only time I typically go up underneath of an intake is if I'm doing a you know a bulkhead connector where I can tie the whole intake harness to one connector where you just spin off one connector and then the whole intake can come off but in this application I'm going to go up and around right so it's easy you know let's pull the intake on this thing you have to unplug this you're going to have to anyway right let's take it set it off to the side out of the way unplug your injectors up underneath the backside of the intake and you pull this thing racing for a long time really being around a lot of small-block nitrous guys or nitrous guys with carburetors being around them for a long time you learned that that nitrous guys are really good at blowing stuff up and especially with the carburetor and and you wind up working on these things in throw action on it maybe slogan shovin slugs into them or you know having to repair the cylinder head or something so you see a lot of this happening so so my thought process is always to you know think about if I've got an hour or two hours to make the next round and we got to change whatever something you know to mean anything maybe a lifter or something I want this I want the guy who owns every car that I work on to when they start taking it apart to go man okay this makes sense this just this lays out the way I would expect it to this is you know makes it nice and easy to work on so have that thought process in your mind that's why the Terminator harness is so nice because and I'm terminating harness you can make it how long you want routed every which way everywhere you want you know as for what's in here to be honest the thought here is getting all this stuff up out of the way right so you know if you got to pull this transmission if you got to pull this transmission right well guess what transmissions coming out of it's coming out this direction okay so litter in the floor up through here with stuff right relays or whatever right doesn't make much sense because you got to pull the transmission out over through here through the door on this car alright so how many times have you pulled the transmission and never dropped to anything it's probably zero so I like to keep stuff high and tight out of the way so that this floor space is used as a floor because you're going to drop tools you're going to you know I don't I didn't mount any of the components in this thing except for what's on this door panel here the ECU is already mounted but uh but typically I suggest you know to put the stuff up out of the way behind the dash something like that where you can um where you can actually access this stuff like this car if you look up in here this car was a it seems to be a nitrous car and it's got studs welded up all on the bar everywhere right and it was to hold those big big contactor relays right they were there all over the place so I just tried to repurpose some of them you know maybe for a chassis ground or a this was holding a fuse you know so trying to try to use what you can to keep it up and out of the way and it also ones up making it easier to work on right if yes diagnosing a bunch of terminal strips here on the floor or standard relays here on the floor yes that is easy but if you actually pay attention and put forth a decent effort when you wire the car to begin with you should have to diagnose the stuff that's here all right there should be there should always be a better chance of blowing blowing this apart or blow the engine apart a blown apart that drive shaft or whatever a big mechanical failure then there should be you know having to hunt down some electrical wiring problem so put a food into where you mount your stuff put a thong into how you around your stuff because the more cluttered up an area gets the harder it is to work on so uh take up some space you know it's spread it out if you need to but keep it out of an area that's going to be high-traffic for repair so all right I'm gonna start looming this stuff you know taking some measurements and and marking it off and I'm gonna pull it out of the car I'll show you when it's all marked off and then how I you know I cut it back and then we start terminating and the next time the car should be for good so hang tight all right so we got the harness all all sealed up here's the here's the breakouts right so all of our measurements that we took earlier right here it all landed where we where we anticipated right so here's our breakout for our switched ignition would come up here we've got our first breakout for a can bus then our remember we talked about a wire coming out of of j1a - so this is it right here this is gonna be switching our relay on for our coil and injector power that's inside of the harness here I break out the o2 sensor a little bit earlier typically just because this is some big shielded cable it's not very flexible it doesn't like to bend well so I have to kind of break it out a little bit earlier now this is all behind the firewall so your firewall again is right here so we're sealed up we hit the firewall now we exit all based off of our measurements so remember how I was saying we sorry I only got one arm here because I've got a dog who won't be quiet there she is yep she won't be quiet so so anyway I remember we were talking about going along the along the valve cover there that is right here so this lead right here this is going to run right up along the valve cover and then it breaks out it's going to go to our throttle position sensor and then we've got our crank signal here and then we have our coolant temp and our fuel pressure so what I like to do is I like to try to keep as many you know single runs so it doesn't become a jumbled mess back here I wanted to be able to break out before the firewall so that it can make the turns right so get all this stuff can turn whichever way it needs to go but if you can run a few of them together before and then and then break them out closer to where they're supposed to go makes life a little bit easier it's less stuff to get screwed up so our next step is going to be labeling everything right like where it's all you know what everything is so like this is a loyal pressure so gonna put a label on yours as a little pressure and then you know our coils and whatnot and then we're going to terminate everything I'm gonna go over showing you how to terminate the different types of connectors that are used with the with the Holly harness but that's gonna be tomorrow because my dog here is very tired and she wants to go to bed so we'll resume this tomorrow but for now hopefully this gives you you know pretty good indicator of how and where to start I think believe total hours into what I've got here is I think we have about nine hours into this and remember I've done a lot of these so take your time and don't anticipate to get this done in two hours because it's just not gonna happen so alright we'll be back tomorrow alright so we've got I stopped here before I completely sealed all this up to show you guys some stuff so when you're terminating your connections if you're gonna boot him you have to make sure that you you know put your labels on first heat shrink over top of them slide your boot on and then um and then what you need to do is you'll you know you'll strip the wire and then you have to slide the little wire seal on okay so why are seals are they come in a couple different sizes they'll come with your you know your connectors from Holly when you buy the unterminated harness setup but you got to slide your wire seal on first and then you crimp your your end so the reason why one of these is yellow and then the other ones green is because I wanted up using tensile wire here it's a thinner diameter so the yellow wire seal is made for a smaller wire and then you know the green one is for you know txl so both of these wires are 20 gauge but you know one steps old ones ones to excel so it needs two different wire skills different sizes the next thing your this is coolant temperature this is the coolant temperature connector so I didn't crimp this so you can see you know we're gonna have to strip back some wire here put your wire seal on and then you'll take your pin and you know typically you hold it like this grab your crimper right and line it up crimp your wire and then you'll know it so now it's holding it on there but now you got to crimp your wire seal alright so there you go thank you wire seal crimped and if you notice there's an indent here on these right so I pulled the I pulled the seal off of this right the lock off of it but you can see these little tabs push up hopefully you can see that so you slide these in with the indent towards the direction of the tabs and it's kind of a pain in the ass to do both at the same time so slide it up and there you go you hear it click and then take your next one alright mm-hmm whatever I'm not gonna fight with this on the camera anyway you slide it in there and then you put your wedge lock on like that and it holds it in place and then you've got a seal on the back oh you got a lock on the backside that keeps the wire from pulling out so you just spread it in there now GT 150 connectors are pressure transducers the same to the same terminal right but same same process so that's why I left this one the way it is this one's already crimped this one's just got the seal on it and stripped this is just stripped but obviously you have to put the seal on here and then crimp it down and then you'll slide your boot overtop of your pressure transducer plug and seal it up with a piece of heat shrink and now you've got a hole sealed harness so that's for the GT 150 stuff and your you know so Metro pack is pretty similar so here here's one complete right for intake air temp all right there's your little lock that goes in there same thing as coolant temp just a little bit different style connector then the next thing is going to be Metro packs so this is your o2 sensor they're a little bit different style of a of a pin but same deal you slide them up in from the bottom they'll engage a lock in there and then there's a wedge lock on the backside here's your this is for cam so this is a pretty common question about shielded cable so what I did was this one's already done but here's shielded cable so when you strip the outer jacket off you'll see this foil right so there's a layer of foil so what you'll do is you'll you'll tear this layer foil off all right and then you've got you've got this in here for actually this is designed to space it evenly right so what you'll do is you take that and take a pair of flush cutters let me grab some air I've gotta go look at a few pair uh you know you grab your flush cutters and you'll cut this flush all right and then you'll take a piece of adhesive one heat shrink this is how I do this it's gonna take your shield all right you know fold it back and cut it and then you'll take a piece of heat shrink adhesive one heat shrink and you'll end up like so so now your shield is down here it's true it's not terminated you don't terminate the shield you leave it open and then take a piece of adhesive lined heat shank and you know shrink it down after you put your after you put your your wire seals on and you crimp your terminals and again same deal this is the connector metro pack they slide in from the bottom they lock in I haven't terminated the coils yet because like I said earlier I'm probably gonna remake the customer provided call harness I'm not too fond of them unless I can figure out a way to make them lay up the way I want but there's all your breakouts this is you know how you do it now most you guys are gonna watch this and go man up I can't I can't do all this and that's that's fine I'm not telling you all to go out and buy you know three thousand dollars of the supplies to build your own harness substitute all of this they see how it's all sealed up for you know a good like split loom or non split Lou seal it all off with a you know a cheaper heat shrink you don't have to do some professional-grade stuff I just was showing you the hardest way to go about it so that your job is easier I don't expect or anticipate y'all to be watching this and going oh okay well I'm just gonna go drop you know a couple thousand dollars on supply so I could build one harness there's no point I was just I wanted y'all to see the heart if I show you the hardest way to do something when you go to do it yourself it's a heck of a lot easier so well yeah that's that's all I got so I'm gonna finish this thing up and plug her all in Oh before I forget when you're making your own harness so injectors right so this is our injector plug just something you know a little a little tip here that makes life a little bit easier all these connectors they know you know almost every single connector this one here is labeled ABC the Deutsch connectors are labeled one through however many pins are in the connector if you're like I use a 12 pin but the Holley harness comes with a 10 pin metro pack for the injectors since if you're making both sides like if you're making the injector harness and then you're making the main harness colors don't matter but position matters right so if this is one then that should go to cylinder one two should go to cylinder two and so on and so forth it's just a little easier for you so that's that's the way I build them it's a little easier to you know to make sense that hey your position one goes to cylinder one I'm if you're using a pre-terminated Holley harness then follow the other side of it right if you use it a pre-terminated Holley injector harness I should say you know follow the other side of it so that's all I got so hopefully that answers a bunch of questions for y'all on how to build your own injector horror your own main harness from a unterminated kit from Holley this is remember this was back here where we're we're gonna hit power relays for four coils injectors and I have I'm segregated by Bank right so coils and injectors on the left side and then the right side and then here's our trigger wire for the relay that's it plug got man hopefully all enjoyed it learn something and my girlfriend of course is going to want to finish off this video by chilling Mushu asleep oh oh she's awake now okay she's mad so we gotta go see ya

Channel: devin vanderhoof

Views: 30,702

Keywords: Holley, Holley efi, Dominator, Hp, Wiring, Automotive wiring, race car, Terminator, Terminator x

Id: o8693ZJGQ5M

Length: 75min 44sec (4544 seconds)

Published: Fri Mar 13 2020