383 Stroker Engine Build part 1

hey guys welcome back to the shop I today we're going to talk about a 383 I'm doing a 3d 3 stroker engine and I thought I'd do a series on it so I'm going to kind of walk you through this step by step we're doing it's a small-block Chevrolet was a 350 engine originally and we're going to build what we call a stroker engine basically what we do is we lengthen this stroke or the distance that the trouble the piston travels in the cylinder I'll buy about a quarter of an inch it increases the cubic inches of the engine and it also increases the power quite a bit so one of the first things you want to do if you're going to build a stroker engine is you you need to get your rotating assembly balanced okay so a couple things about a stroker we got our our balance job here this is actually what would be considered a balance job so what you need for a stroker engine is you need your harmonic dampener balancer this is a balancer made by professional products and it actually has a weight in it that it's a it's a bolt in weight you can actually trim this weight or get a bigger weight if you want to depending on what you need to do the the 383 uses a 400 small-block crankshaft which is a it's an externally balanced engine now you can build these internally ballots you get an internally balanced crankshaft aftermarket crank but this is not really that high of a performance engine this is a street rod engine and so we're we decided to go with because the customers on a budget because of you know budget constraints we decided to go with the externally balanced crankshaft because it was actually more cost effective it was less expensive so you're going to have to have your harmonic balancer you also are going to have to either your flywheel or flexplate this is an automatic transmission in this car so we decided yeah we have a flex plate your pistons and connecting rods now stroker pistons are a little different what they do in a stroker engine because they're putting a longer stroke into the engine today the stroker piston actually has a pin that is relocated in other words a 350 pin will probably be somewhere in here but what they've done with the stroker is they raise the pin location what that does is that allows the piston and sit down inside the motor below the deck or at the deck surface with the piston the top dead center because if you just add stroke to the crankshaft and you use the same Pistons the piston is basically then pop out the top of more so what you do is you have to get a stroker piston that has a compression height now compression height is the distance from the center of the pin to the flat part of the piston on top that distance so if I raise the pin up that's going to lower the piston down in the cylinder and they calculate how much that is depending on the rod length that you're using and the stroke of your crank in this case we're building the 383 so we're using a three and three-quarter inch stroke crank three point seven five oh so because of that we've had to buy pistons with a raised location and these Pistons are designed to work with a connecting rod a 350 rod which is a five-inch 700,000 rod and a three and three-quarter inch stroke so hopefully that makes sense so what you need to do is you need to get all these parts together once you decide you know just exactly what your compression ratio and so forth is going to be I'll talk about compression ratio later in another video but one of the things that you have to do it's mandatory is you have to get your stroker rotating assembly balanced it's this is not optional the thing is going to vibrate like crazy if you don't to it so let me explain balancing to you what balancing is is it is an equalizing of the weight of all the components so what we're going to do is first of all we have a scale that actually goes down to very small increments we can get down to about a tenth of a gram now a gram is about the weight of a dollar bill doesn't seem like much weight but you got to remember when an engine is running the faster the RPMs of the engine are the heavier the parts get now the parts don't actually get heavier but when this thing is moving you have rotating mass the force that is exerted on the internal parts in the engine is very similar to those parts weighing way more than they actually weigh so a gram of weight or two grams or three grams just statically on the bench actually calculate calculates out to being a lot more weight than that when this thing is actually slinging back and forth and all the stresses are you know pulling and pushing on the rod and everything else a few grams off can actually make on a high rpm engine can make a big difference it can actually cause the engine to actually fly apart so everything has to be perfectly balanced because the higher the RPM of the engine is or at higher rpm these components are under incredibly high stress and so balancing is important so what we do when we balance now this engines already been balanced is we're going to take all of our pistons we'll just take in this case we have eight Pistons we're going to take eight Pistons and we're going to put them on a scale that's very sensitive goes down to about a tenth of a gram we're going to find the lightest piston out of the bunch and we're going to use that as our reference so we take the lightest piston we set that on the scale and we use that light piston as a reference now you can see if you look close on this piston this piston has actually been had some material shaved off of it right here so what we do is if this was actually one of the Pistons that was a little bit heavier and so we took and we used a sanding tool and we actually lightly remove material from this skirt so what you do is see you have a reference piston that's lighter than the rest and use it so I weigh this piston and it's heavier let's say it's three grams heavier then you know that my standard piston or my piston I'm using as a reference well then I'm just going to start shaving material off here and put it back on the scale now not enough I'm going to shave a little more no not enough so I basically shave this off until I have all of my pistons weighing exactly the same weight within about a quarter of a gram which is very very close then I take the piston pins' and I do the same thing I'm going to weigh all the pins on the scale and I take and I can shave material off the ends of the pins until I get all the pins weighing exactly the same so now I have eight Pistons and eight pins that all weigh exactly the same then I move on to my connecting rods I take my connecting rods and I do the same thing I weigh each rod once I find the lightest rod out of the eight I use that as a reference and then I start shaving material if you look at this rod you can see that it's had material shaved off of it we shave off of the balance pad on the cap and we shave off of the balance pad up here so these rods have all been balanced the weights been equalized on all of them so they all weigh the same when we weigh the rods now one thing that's important to notice when they weigh the rods they actually weigh the small end and the big end separately so they're going to they're going to hang this on there this is going to just hang here on a hanger and this is going to sit on the scale we're going to weigh all of the small ends and we're going to equalize the weight of all the small ends then we're going to flip it around hang the small end and we're going to put the big end on the scale here and we're going to weigh that the reason we do that is because we have two different types of motions up here we have reciprocating motion this is going up and down and down here we have rotational motion so in order to get the balance right we actually have to weigh these independently or separate when you're done if you do it correctly all the rods will weigh the same so now what we have is we have eight Pistons pins and connecting rods and they all be exactly the same what I do at that point then as I take my connecting rod my piston my pin and I take and I lay all these let's say this was your scale here I just lay all these on the scale and I weigh them together I also have a couple other factors in there that are that contribute to the weight and that is my rings so the Rings that I'm going to use in the engine I go ahead and I throw the Rings on the tail - the other factor that we have is we have our bearings so you're going to take your connecting rod bearings for that the controls are actually inside the scaler so we take our connecting rods rod bearings because the bearings of course are going to be in the big end of the raw so put all this stuff on the scale we'll take our our bearings then we get a reading this is called a now when you go into a battle shop if you you can buy a one of these scales yourself and actually weight match this stuff it might be more effective though or more feasible just to have the machine shop to it but one of the things if you do happen to weigh this stuff yourself one of the things that the shop Lasky when you walk in and they'll say hey you know what's your Bob wait what's your Bob wait now well what they mean by that is how much does all this way and they will actually add a small amount of weight for the oil that is going to be on these components in the engine the oil actually has some weight to it so they'll add a few grams of weight for the oil well your Bob Way is basically what this stuff here way after it's all been equalized so in other words it's been equalized so all of the rods all of the pistons and of course the Rings and the bearings are match set so all that stuff weighs the same so all of this combined might connect basically my piston rod assembly with its rings and bearings that amount of weight is my BOB weight plus the oil that they calculate in so then what they do is now this is our stroker crankshaft here it has a longer stroke crank the way it struck on the way a stroker works is the distance from the center line of the main journal to the center line of the rod journal is actually longer so what that does is that makes this journal sway further which in turn makes the rod travel further in the cylinder I have more stroke or a longer stroke so this is our stroker cranker we've got a pub we've got a balance we've got it ready to go so what they do is they take weights now they take our Bob weight that we've calculated and we're going to pull weights that are designed to go on the journals here because you can't really if you're going to spend the crank on a balancing machine you can't really bolt your piston rod assemblies on it's just not feasible to do that so they have special weights that go along with their balancing machine and actually bolt on here and the weights are adjustable they can add or remove weight as needed what they do is they take your bob weight and they put weights on here that's equal to the weight of your piston and rod assembly and you're actually going to have the weight of two of these because we have two rods on here once they do that they put the cadet they put the crankshaft in it and a computer spin balancing machine and they spin the crank and the computer looks for imbalances the computer will tell the operator whether or not we are too light or too heavy here now if you see if you look at the holes in this this throw here on this crankshaft this counterweight what they've done is they've taken them hols out here the reason they did that was because this was actually too heavy so they had to lighten this up the idea is that when this thing is assembled I'm going to have two connecting rods on here one going to each bank plus I'm going to have to piston two pistons and rings and the piston pin and everything hanging off to that journal opposite this crow so they are going to equalize the later they're going to make this counter weight equal to the weight of those two piston rod assemblies that are hanging off of this crank and that way as it rotates it rotates smoothly we don't have any imbalances there if you had a piston piston and rod assemblies over here that were either heavier or lighter than this weight then your your engine is going to vibrate like crazy which is exactly what would happen if you just took 383 parts then you've got it you've got an aftermarket skat crank like this one and you bought a set of Pistons and you you just purchase this stuff that's designed to go with a 383 and you just slap it together in the engine without any balancing there is no way that these components are going to weigh the same as this so you're going to have an engine that vibrates like crazy and probably will destroy itself very quickly so the and and when they spin this up again keep in mind they're also going to put the harmonic balancer on the front and they're going to put the Flex later flywheel in the back and they're going to spin the whole thing with the bob weights on here on the machine and they're going to balance it out once they get everything equalized they all of the the crank throws here either lightened up or they can actually add heavy metal to these if they want to they will usually drill down here and press heavy metal in here if they need to make more weight there so they can go either way they can lighten it up or they can you know make it heavier regardless of what they have to do balancing is actually essential you need to find a shop that's really good that has a good reputation because not all balance jobs are equal your balanced job in my personal experience should be down to about a quarter of a gram okay if they're balancing now the factory balance is that you know you hear that term thrown out to owe you that what you do yours you know we have well I had a balanced and blueprinted man and talk about balancing like it's something that only is done to high-performance engines well there's a little bit of truth in that but not really every engine is actually balanced from the factory but the balanced job that they do on a stock OEM type vehicle is not going to be nearly as precise as a high RPM street rod motor or a race motor because you know I've seen balance factory balance jobs where the components when you weigh them were off by you know 10 12 grams well that's fine for a stock engine that's going to turn low rpms and it's just it's a daily driver daily driven stock type OEM engines that are in you know stock passenger cars and pickup trucks people commute in them or whatever they're they generally run at very low rpms but when you're building a high-performance engine you're going to be renting that engine much harder there's going to be a lot more stress inside the engine it's going to turn a much higher rpm and so a good performance balance is going to be within a 1/4 of a gram and so if the machine shop that you're working with can't do it within a quarter of a gram and I'd find a no chop because there's plenty of shops out there that can do it within a quarter of a gram if they have the right equipment and they have a you know a skilled machinist that can do it so that's basically balancing in a nutshell when you get your 383 stroker parts and you buy your kit which this all came in a kit keep in mind you are going to have to have now you can buy kits that are balanced but I would caution you on those my experience with kits that are balanced right out of the box a lot of times it depends on where you got that kit from and how they are how technical they are on their balancing I've gotten some balanced rotating assemblies for the stroker engines before and I actually check and weigh the stuff out of the box and man the balance job they were off by you know three or four grams which is way too much for a performance engine and I actually had to take that and get it rebalance and have somebody who was really good at this I have a guy that does it for me and so find some shop I would find a shop locally that you can you know deal with and talk to that actually can do a balanced job to within one quarter of gram and you know they're out there they're out there so that's basically balancing in a nutshell so you hear people throw that term out there balancing and blueprinting okay well what is blueprinting blueprinting is basically just measuring all the specs of your engine blueprinting is is another thing that people say well you know this hinge is really special because it was blueprinted every engine that's ever built needs to be blue printed that just means you measured all of the components and you documented the measurements and the clearances and made sure that they were within a specific tolerance that's all blue printing is blue printing is documenting the sizes of the engine and it's a good idea to document that and write it all down also with balancing that Bob weight that I talked about the weight these components here the balancer will usually give you a card that has all the Bob weights on it and has you know all of the weights of everything here it's a it's a basically a scorecard of you if you will of everything that they weight and and how it came out on the balancer hang on to that because if you run into a problem where you break a piston or you break a connecting you have to change something on that you're going to have to have the engine rebalanced again as a matter of fact this stroker engine that we're doing here this is the second time around on this engine this engine had flat top Pistons in it we're going back in with a dish piston on this time because it had flattop Pistons in it and the compression was a little too high the customer the the guy that owned the car was running pump gas and he detonated the crap out of it because he had way too much timing put into the ignition and also you have too much compression for the fuel and it actually blew a chunk of aluminum out of one of the Pistons and busted the cylinder so we're going back in this time we're calculated we calculated the compression ratio usually when you build a stroker you're going to put a dish type piston in and of course it depends on what heads you have and so forth but this end this engine is actually getting a set of dart heads that have you know closed chamber it's a small combustion chamber so we want to keep the compression raishin ratio down and it depends on what kind of fuel you're running but he's running pump gas so we want to keep that compression ratio down around nine and a half to one so we can put pump gas in this thing so you know there's a lot of factors that you need to think about when you go through strokers and we're going to talk about that stuff the next couple of videos I'm going to be working on the block I've already got the block board vatted and magnaflux tan board it's a real good candidate I'll show it to you here this is our 383 block so we are going to have to deck the the the surfaces on and of course it's it's bare right now it has been cleaned and board but we still have some machine work and another thing is we have a lot of clearancing that you have to do with this the stroker engine one of the other things that we're going to talk about and actually probably make some videos on is the fact that the the crankshaft when you put a longer stroke crank and a stroker engine what that does is that makes the rod sway a lot further and a lot of times the the block itself will interfere and you actually have to pre assemble this engine going to be going to do that and you have to use clearance putty and you have to basically look at all the spots in here where this connecting rod could contact the block and you have to go in with a dremel and you have to relieve the block in that area we want anywhere from 80 to a hundred thousands clearance cold on this thing because everything swells up when it gets hot so block clearancing is another thing people wonder why 383 s cost so much you know you can get a basically a pretty decent 350 for anywhere from 12 to 1500 bucks and then you start getting into these stroker engines you know it's four or five six thousand dollars and people like well you know it's just a small block why's it so much because it's way more work to put one of these together in the end it will be worth it if you do it correctly and you'll have a very nice engine with way more power than you would ever get from a 350 if it's done right but there's a lot more work that goes into it can't just start slapping this stuff together and so hopefully you'll stay tuned for this series because I'm going to I'm basically going to build this entire engine on video I'm going to when we're done we'll try to get this thing on the run stand and fire it up for you and actually do the initial runnin of the camshaft and we'll talk about what type of cam we're going to put in it and all that stuff in future videos but very important just keep in mind the balancing concept and that is if you're going to build a stroker engine you absolutely have to balance the end to get this thing balanced so if you have any questions be sure to ask below I'd be happy to answer your questions also be sure to subscribe that way you don't miss anything because it's going to be a great 383 series and hopefully we'll see you next time thanks for watching

Channel: Myvintageiron7512

Views: 226,186

Rating: 4.9063492 out of 5

Keywords: 377, Racing (Musical Album), YouTube, 347, Dodge, Chevrolet (Brand), Mustang, Rat Rod, Supercharger, Nissan, NASCAR, NOS, Small Block, Honda, Stroker Kit, Turbo, 383, Mazda, Chevy, Racing, Ford (Geographical Feature Category), Ford, 331, NHRA, V8 Engine (Engine Type), F150, Big Block

Id: oL7tcTlzCt8

Length: 23min 35sec (1415 seconds)

Published: Mon May 12 2014