S2E7: Moar Boost Cap’n! We Road Test the 420cc Street Legal Go-Kart with AMR300 Supercharger!

[Music] welcome back to robot cantina a cement mixer powered street legal gold cart with a stupid charger what else do you need to know grab your coffee and donut and let's get going oh yeah don't forget to shave now today i'm going to need you to be on your a game and pay attention we got a lot to cover [Music] so for the stupid charger experiment we're going to use the spare 420 inch that we have in stock this engine is brand new and has never been run so we mounted it on one of our test stands and let it run for a few hours to break it in now this engine has a regular carburetor and a magneto ignition system both of those are necessary to break the engine in but after we build it it'll be set up with the speed duino fuel injection that we've been running in our street legal gold cart since last summer the stupid charger will certainly put a lot of stress on the engine so we're going to reinforce it with an arc billet connecting rod along with stainless steel valves and some heavier valve springs of course new gaskets and all the necessary stuff to put it back together when we're done it'll be ready for boost now speaking of boost we'll also need to modify the stock piston rings and for that we use this grinder thingy along with a feeler gauge and we'll get back to that in a few minutes but the first thing we need to do is strip this engine down to the bare block are you guys ready [Music] okay so this is something i do and it really bugs me when people mix up valve train components anyway i like to keep all the parts together so when i reassemble the engine all the parts go back in the same location on a brand new engine like this i don't think it makes a difference but it's good practice [Music] so at this point we can remove the last few components and that is the piston and connecting rod so the stock 420 rod looks pretty beefy but we'll replace it anyway now check this out i'm sure it makes sense to whoever engineered this part but look at how they remove material or both halves of the rod mate i reckon this is to help with the lubrication or something the arc rod on the other hand this is a piece of artwork now arc doesn't sponsor this channel and i'm not obligated to say good things i just feel the need to say something nice about a product that makes today's experiment possible without this rod i think things would probably end rather quickly anyway this rod has a little scoop to force the oil into the bearings i don't know if that helps but it's a nice feature for sure now this rod also uses automotive type bearing inserts which is also a nice feature so with the electronic fuel injection we don't need the governor that's built into the engine so theoretically we can remove this plastic governor gear my only concern is this gear also serves another purpose because it flings oil around when it spins ultimately i feel the plastic gear is a liability and has to be removed so that's what we'll do now getting this gear off is difficult at best i actually went over to redbeard's channel and did some learning or something like that the takeaway is you have to bust the gear in many pieces to get it off so fast forward a little bit we have the busted gear this little clip is what holds the gear in place and you pretty much have to demolish the gear to get it out so let's take a look at the piston rings so on a turbo or supercharged engine the piston rings see a lot of heat and from what i've read on the internet it's good practice to open up the ring gap or else serious engine damage can result the procedure requires first measuring the current ring gap and then applying a formula to calculate how much to grind off the formula is different depending on what type of engine you're working on for instance the water-cooled engine is different from an air-cooled engine and diesel engines are different as well the prevailing thought is the piston rings see a lot of heat and can expand faster than the rest of the engine if they expand too fast well the ring gap will close and the ring will bind and push outward possibly seizing the engine or something will get busted in a bad way so to avoid the issues of insufficient ring gap we need to shave a few thousands off the rings with this thingamajig the camera guy decided to show up and lend us a hand which was nice anyway it takes several attempts to get the ring gap correct [Music] the last part of this build is putting the cylinder head back together now we're using brand new stainless steel valves and we'll need to lap them in i like to use machinist blue when doing this if the valves are lapped correctly there should be no dye left on the contact points it's a good way to detect problems early in the build lapping the valves requires a little bit of grit and you just smear it on the valve this will help mate the valve to the seat for perfect fit of course you'll have to clean this stuff off when done or you'll have a bad day putting the valve springs back in takes a lot of effort fortunately the store that sells the predator engine also sells a cheapo valve spring compressor kit you know i never mentioned the store by name in any of my videos anyway with the cylinder head complete we can put the engine back together and install the stupid charger so let's take a moment and talk about the supercharger for today's experiment we're going to install an acen amr300 now that's a roots type positive displacement 300 cc supercharger so what that means is every time the supercharger makes one revolution it'll pump 300 cc's of air this type of supercharger differs from a turbo in that it offers instantaneous boost and doesn't need time to spool up or in other words as soon as you floor the accelerator you're making boost and we want boost now not a little bit later so inevitably someone will ask why don't you use a turbo well originally we were going to use a terrible but we don't have a reliable way to generate oil pressure that the turbo requires and that is because our 420 cc engine doesn't have an oil pump and yeah i'm aware that an electric oil pump could be used but in my opinion that's a little bit more than half ass instead we're going with the stupid charger because it has its own oil supply and doesn't need an oil pump of course some would say that the newly released predator 459 does have an oil pump and yep i'm aware of that but today we have a supercharger and a 420cc engine so let's install the stupid charger and see what happens anyway this is the 300cc variant and there's also a 500cc supercharger now these things can be purchased for less than 200 bucks on various websites that sell things so they're pretty easy to get if you want to experiment with one so today we'll experiment with the amr300 and by the end of the video we'll see if this supercharger works or what modifications we'll need to do in order to make it work better but the only way we'll learn is to try and possibly fail so here is the supercharger now keep in mind these things are cheap because they're used and allegedly remanufactured now this one appears to have been cleaned up a little bit but i'm not really sure was actually rebuilt it is what it is of course there's the output side and if we flip it over there's the input so that's something important to be aware of and it should go without saying so this shaft sticking out is for the drive pulley originally this came with a cast iron v-belt pulley and that was probably fine but we machined the pulley down to a flange to give us different pulley options plus we wanted to use a flat belt instead of a v belt it's just a matter of preference really now the pulley we're using is from a ford v6 and i believe it's a water pump pulley anyway it's a starting point and we may have to go with a smaller diameter pulley depending on how much boost we generate currently we're starting off with a one-to-one ratio and that's what the folks in the comment section suggested several episodes ago back in season one yeah this supercharger experiment has taken a while to get rolling so a one-to-one ratio kind of makes sense and that's why we went with it keep in mind at wide open throttle the supercharger delivers a 300cc chunk of air every revolution and in a perfect case the engine can consume 420 ccs of air every two revolutions so theoretically we have a surplus air and that spells b-o-o-s-t now i'm sure it's more complicated than that but i feel it's a good starting point so if you would take a moment and put down your best guess in the comment section whether this will make boost or not so the pulley gets attached with a few fasteners for a secure fit for the input flange we took the plastic doohickey that the supercharger came with and machined off the stub now we did this to save space because there ain't a lot of room under the hood of a honda insight these cars were built to a minimum and as light and aerodynamic as possible but inevitably some yahoo comes along with a gitter down attitude and we can get stuff to fit well most of the time the jury's still out on the 670v twin the throttle body mount on the input side of the supercharger was achieved by using a small block chevy water neck it's almost the perfect fit and this custom part costs 20 bucks the water neck has an o-ring on the flange side that makes an airtight seal once it's bolted up to the supercharger the throttle body in itself is from an unknown motorcycle engine basically i saw it on ebay and thought well this looks like it'll work and since it came from overseas the language barrier prevented me from getting any specific info on this part so if anybody knows what this is from let me know the throttle position sensor that came with the throttle body had a weird connector on it so once again i jumped on ebay and did some digging i couldn't find the correct connector but i did find a new tps sensor from a polaris ranger 700 the polaris tps sensor has a short harness and a connector so i ended up cutting off the connector from the harness and installing a generic connector it works for the output side of the supercharger we use the water neck from an unknown car basically i found this water neck laying on the ground at the pick and pull and snatched it up a small block chevy gasket seems to fit it perfectly so it may be yet another chevy part the inlet air temperature sensor or iat needs to sample the air temperature after the supercharger because the compressed air will get significantly hotter once it passes through the supercharger so for the sensor i use the standard gm type sensor and to mount it i use the 40 millimeter aluminum radiator coolant hose joint these joints are normally used to add additional coolant temperature sensors but in our case it was the right size for the induction pipes we're using so it got repurposed the injector housing we're using is again from an unknown type motorcycle engine i'm not sure but it looks like it's made from abs plastic and may or may not be suitable for our application only time will tell the o-ring pocket was eventually filled in with jb weld and the flange was sanded smooth so we could use a larger gasket a little bit of fiddling went into this joint to produce an airtight seal of course this is where the injector mounts and this is the nipple where we connect the map sensor so this little plastic manifold attaches to the 420 engine with this custom-built aluminum adapter again everything is a tight fit with awkward angles but in the end it all lined up the last bit of the supercharger upgrade was finding the way to mount the drive pulley for this we used the hub from performance 670. this hub was originally intended to mount a drive shaft on the flywheel side of a 420 predator engine but with a little machining we were able to mate it up with a ford water pump pulley not too shabby so as you can see for this build we tried to use a lot of off-the-shelf parts when possible but there was a lot of fabrication involved to make this system compact so it would fit under the hood of the honda inside and leave us room for possible future upgrades like an intercooler or whatnot now this system may look huge on the bench but like i said this is how it all fits together when it's in the car i say we fade to black and in the next scene we'll see if the engine will run with all this random stuff [Applause] [Music] [Applause] well crap a rookie mistake i reckon but the good news is the engine started and that was half the battle [Applause] so the problem's obvious once you wrap your head around what's going on since the throttle body is ahead of the stupid charger at idle when the engine generates vacuum the induction hoses are collapsing it doesn't matter how fast the supercharger spins at idle because the throttle body is choking off the air supply we could spin the supercharger 10 times as fast but at idle the throttle will still be closed and it wouldn't let in enough air to inflate the induction pipes this appears to be an issue just at idle and it makes sense once you put your mind to it so there's many ways to fix this i elected to reinforce the induction hoses with aluminum pipe i sourced a few feet of aluminum tubing and cut it in sections to fit inside the flexible induction pipe each piece had to be cut to the exact size and then deburred on the lathe it took some effort but the end results kept the induction plumbing looking nice now i'm kind of getting ahead of myself because in the time it took to get the aluminum pipe to modify the induction system we went ahead and mounted the throttle body directly to the engine and bypassed the stupid charger we did this so the car could be driven and we could collect some data on the new throttle body long story even longer while out driving we encountered yet another problem this time it ended up being the brakes we're not releasing all the way well we ended up replacing the seals on the front calipers and that made a huge difference so here's something i noticed when bleeding the brakes let's see if you can spot it yeah so this car has the calibers mounted in different locations it turns out the driver side of the car has the wrong spindle on it a new one is on the way but since it worked before it'll work again and we'll run with it for now when it rains it pours so with the induction plumbing reinforced it was time to see if this thing would actually work let's take a look well that's good enough for me keep in mind the engine's running on the previous tune and isn't set up for the supercharger yet so it's running a little rough but that's easily fixed so this area here is part of the ve map that we needed to modify just to get the engine idle now the rest of the map is completely wrong but for now all i want is the engine idle i'll deal with setting up the rest of the map later so with the basics sorted out it was time to rewrite all the maps for boost now i ain't never done this before so the basics are pull back on the ignition timing and add a little bit more fuel we can fine-tune it after looking at some data log files but for now we're running a safe tune so the boost is still unknown and for safety we'll put a fuel shut-off limit if we see boost above 150 kilopascals or 7.2 psi that should be plenty of overhead because this thing will never make that much boost or will it well i guess we shall see i reckon it's time to get some data [Applause] so right away the car feels different the throttle response is at a whole new level um i think we finally did something right now keep in mind the tune at this point is rough and we'll need to fine tune it as we do some basic testing the minivan in front of me is my brother duke and his wife cheryl and they pretty much have it easy today their only job is to be on standby in the event the engine explodes or something like that duke and cheryl are the other half of the robot cantina team in case you're wondering anyway give this video a thumbs up for duke and cheryl otherwise have been a fire of both [Music] after about a half hour data logging and tuning we were ready to do some wide open acceleration runs well if you recall we previously set the field to cut off if the manifold pressure exceeded 150 kilopascals so 150 kilopascals translates to 7.2 psi i guess the stupid charger actually works booyah just for giggles we set the new limit to 175 kilopascals or about 10.5 psi that should be enough overhead to avoid fuel cut off now let's try that again looking good now let's go ahead and look at some live data so here's the rundown the white is the rpm red is the manifold pressure and anything above 100 is boost green is the intake air temperature now obviously we ain't got an intercooler yet so this is something to keep an eye on and of course yellow is the throttle position sensor for this test we're starting off in third gear and letting the cvt do all the work and we'll take it all the way to 50 miles per hour okay so we're almost ready but i want to point out the throttle position trace normally we floor the accelerator and the tps goes to 100 instantly however this time around we're easing into the throttle because too many unknowns and it's better to be safe than sorry this will affect our times but by how much we shall see [Music] [Music] not too shabby all things considered now let's try this again but this time we'll start off in fourth gear and take it all the way to 60 miles per hour the beeping sounds you hear during the acceleration run marks the different speed levels for instance the first beep you hear is 30 miles per hour the second is 40 then there's one at 50 and of course one at 60. and keep in mind on this one we also eased into the throttle all right let's do it do [Applause] so how'd we do well starting off in third gear and easing into the throttle with less than an ideal tune then it does 32.85 seconds to reach 50 miles per hour so how does that compare to the previous times well good question now this might surprise some folks but the best time we previously recorded was 33.23 seconds so we're about a half second faster but keep in mind the car was severely handicapped being this was its first outing with the stupid charger i reckon it'll be easy to cut five to ten seconds off this time or not depending on how much we exceed the design limitations of all this crap we put the car together with it'll be interesting the stupid charger generated a very respectable 7 psi of boost during the run and we saw a peak at 10 psi right before it hit redline now we would be jumping for joy at 5 psi and this was completely unexpected so did any of you folks guess correctly honestly this was a tough call and it's okay if you got it wrong the intake air temp looks like it's going to be a problem but i'm no expert anybody think it's time for an intercooler now these data plots have been simplified for the general audience and of course there's a lot more going on that we also have to look at aside from the air temperature the only real problem i can see here is the vacuum when the throttle is closed well normally vacuum ain't a problem but as others have commented before the seals and the supercharger may not be engineered for that much vacuum so we have a few tricks we want to try so the takeaway is yes the stupid charger works and we ain't broke nothing yet it was definitely a good day so 0 to 60 when starting off in fourth gear well that's a different story you see we've never done that before because previously there wasn't enough road to try this it takes a long time when starting off in fourth gear today is of course a day of great surprises because this car didn't let us down it didn't break and it got us up to 60 miles per hour and less road than it takes to get a 747 off the ground the stupid charger really shined on this one zero to 60 took 59 seconds and for the metric crowd that's less than a minute that's pretty much meaningless without something to compare to and the best we can show was it took 89 seconds to hit 60 when starting off in third gear but that's apples and oranges but still what about top speed well we didn't push our luck and that's something for another day now do i think the car will go faster than the 70 mile per hour goal hell yeah and we'll get there but not today we have some work to do with the tune and whatnot and make some doohickeys and so forth but we'll get there be sure to leave comments and inevitably there'll be those who ask why i didn't do it this way or that way well i did it my way along with the help from all those who leave comments but i can't completely re-engineer on the fly to satisfy everybody this channel doesn't have the resources like the goon squad which i truly love to watch anyway with the more subscribers the more we can do it's just that simple so if you haven't subscribed already please do so if you want to see a 420 cc fuel-injected supercharged hemi from a cement mixer get this honda inside up to 70 miles per hour until next time what are you going to make now the video is over you'll see [Music] oh that is cool come on buddy let's go get some lunch can we have motor oil it's engine oil and yes you can have some

Channel: Robot Cantina

Views: 265,340

Keywords: $99, 212 cc, 420 cc, 420 hemi, alternative transportation, custom, cvt transmission, diy, documentary, efi, electric car, electric vehicle, engine mods, engine swap, fabricate, fuel economy, fun, funny, go cart, megasquirt, gocart, gokart, NO2C, goonzquad, great idea, gx390, hack, hand made, harbor freight, hemi, hho, high performance, home made, homemade, hp, hybrid, lada, lawn mower, lawnmower, modification, modify, motor, motor swap, motorcycle, mpg, predator powered car, Fuel injection, speeduino

Id: xehLStb4vZQ

Length: 26min 40sec (1600 seconds)

Published: Sun Apr 24 2022