Turbocharging My Honda 400ex 2.0 First Ride (New Design + Upgrades) 

Joe, what i see for this project is sitting on the back burner for a bit, you researching and designing a more streamline turbo setup for this quad and when nobody expects it you pull it out and just dominate. Never give up, Dont lose sight!!

That exhaust mount just hanging there in the breeze on the exhaust pipe is driving me nuts dude.

Just got my first bike!!!, So happy, thanks for all the knowledge, been watching for a couple of years and feel like I have a pretty good understanding of the maintenance thanks to you and others, 2 stoked!

you have to have the fuel right for the right amount of boost and i dont think that carb can handle that fuel. CUT THE BOOST TO 4 PSI AND YOULL BE FINE

Loved following along on this project. You win some, you lose some, but definitely learned a great deal. I suspect you'll accidentally run into some info that will tie this puzzle together. Thanks for sharing.

Put it on injection get it running right, then add the turbo, then change the map to suit the turbo, you will always be fighting it with a carb, it should be much simpler than this!

Did u lower the plug gap and make sure there is no boost leaks. Is there and air fuel gauge on there? Will help tell u if it's to rich or to lean. Careful man playing with fire shall we say can blow up easy during this stage. Good luck man keep it up.

about to go down this rabbit hole with a 400 stroker yfm350r. thank you for getting this journey started for all of us

Brother ive been watching your stuff for a while now and always love and respect all content, anyway if someone is able to achieve this it could absolutely be you my man just may need a bit more patience and im fully confident in your ability to get it done!! That said im kinda curious if you can convert from carburetor to EFI and maybe thats the extra step to making it come to life 🤔. Good luck man and keep on sending it bro, thanks for all you do💯🍻

Man I was really hoping u had gotten it right .dont give up 💪💪

Never give up!!! You're SO close!!!

Don't give up man, it takes time, good video

Love it keep grinding bro love the content

The carb is designed to have air drawn threw it not pressurized. Put the carb before the turbo so it can suck the fuel in :)

Been one of your best series2. Don't give up mate. Lower boost or different carby. Over 50k people wanna see you get it craking

It’s definitely almost there don’t give up on it, the boosted bois did a turbo 400cc in a shopping cart maybe you can get some info from that video. I’m not sure if it is hurting you in this situation but maybe a ported head would help out

Keeep at it man!!!!! Gotta be a fuel problem. Somehow the fuel has to be maintained.. Hope ya keep it going.

Most fuel pressure regulators use a return line. Excess fuel is sent back to the tank. Check to see if yours requires a return. Fuel comes from the pump to the regulator . The regulator then sends desired pressure to the carb and returns excess pressure back to the tank. I wonder if that kinked off line is intended to be your return. Great job, you’re almost there.

The carb slide works on vacuum which isn't compatible with your setup, u would try a different carburetor with a manual slide. Don't give up you've come this far. Also it would be a big help for you to learn to read your spark plugs, they can tell you a lot about your air fuel mixture and other thing going on in your engine. Keep up the good work.

Like others have said, don't give up. It just needs to go on the back burner for a bit so you can regroup. You have a brilliant mind and I'm sure you will figure it out in time.

I'm sorry about that man, you did really good and you sure made some good videos on it! I'm excited to see what projects you start on next.

Eey man. Love your video’s man !! I think the pressure regulator needs a return to tank so it can bleed pressure

Get an oil restrictor for the turbo. Fuel pressure needs to be zero when not in boost. If you can't get it to zero then set it to say five psi then rejet for the extra fuel. Smaller pilot lower needle exc.. then use the regulator to raise the fuel pressure per pound of boost. Last but not least get a afr gage. You could use it tuning your other quads also.

don’t give up yet. you got this!!!

Watched all the vids and Damm I wsh you got it right it was awsome

Wow amazing engineering and creativity

Love the videos keep head up if anyone can do it it’s you keep up great content

Don’t give it up build it up very cool content love it❤️

Good concept good content what u need is a independent control module (computer) fuel injection heavier valve springs? I would look into maybe go-kart fuel injection systems single band wide band 02 sensor? Just kicking around some ideas either way always informative to watch and entertaining

Hey man you get an A for effort you gave it the old college try and it’s all you can do! Sometimes you eat the bear and sometimes the bear eats you! It was a great build you tried and that’s all you can do👍🏼🤩 so keep up the great work though💪🏼

Couple of questions, should you not have run it in before going back to the turbo to let everything settle before adding boost? Also please for the love of God get rid of that flange on that downpipe 🤣

Definitely a smaller plug gap is needed when you get into boost. Most carbs need a rising rate fuel pressure regulator which raises fuel pressure 1:1 per pound of boost.

Put the turbo between the carb and the engine so the turbo pulls through. Many old motorcycle turbo kits work this way. Its also great for packaging. The carb cant pull fuel out of the bowl if there is pressure pushing it back in. That is why carburetors built for boost are of a much different design.

Hey man I know it's been a while since you worked on this. I hope you read this and take my suggestions! First thing I would have done double up the Cylinder Base gaskets to lower compression, put a "Stocke Replacment" JE Piston in or a Wiesco (I say "stock Replacment" because it's a forged piston with same compresion ratio), buy a turbine style inline Fuel Pump something simular to a Delph CFD0029... I noticed you have th FPR Return Blocked off, that won't do anything no matter what you do the fuel pressure is necause you always need to bypass fuel during idle and when you're not in boost, so plumb the retuen line back into the Fuel Tank somewhere. Now the FPR "reference" needs to be infront of the Carburetor infront of the Carburetor so that wa the FPR will see Vacuum during idle and lower RPMS and then it will get Bost Pressure during boost. Also you may want a Blow off Valve so that way whe you let off the throttle or wanting tp let it idle it opens and 100% by passes any boost that you do not wan't especially during idle it will be able to use Stock Hetting for idling. Now last you need to figure out a way to retard the ignition iming as the RPMS climb. Basicully you wanna think of it like this By pass all Fuel Pressure and Boost till you're into boost. You will also need to sand a more aggressive Taper on the first 12mm of the Slide Need. You do not wanna go wiith bigger jetting like you would think because now that you're flowing more air through which means you will have a much more powerfull "draft" accross the emulsion tube which which fuel pressure will autmaticully draw more fuel into the engine.

Try using a AFR gauge to help you tune it I've used one in the past and they will help you alot when tuning it

This is mostly above me with the tubo so I bid you Good luck my Wisconsin friend and will smile and nod as you adjust and make changes. Lol

🔥pretty cool man, def a killer build. Forsure carb issues. Don’t give up Man U will get it. Stock jetting, no fuel pump, that carb is setup for gravity pressure, get it running smooth first, yes will be lean. Then slowly jet up and keep looking at plug till looks creamy. To me fells like will be hard to achieve it all with a carb setup trying to force all that air flow and moving that fuel into cylinder. Maybe work lil better with efi engine? Just a thought 💭

Might be easier to just trasfer all these stuff onto a fuel injected quad and try with that

Great video

Don’t give up brother.

It’s gotta be that pump. Last one was not enough this one is too much. Gotta be a happy medium somewhere. Definitely just need to take a brake but you have a great following for the project and hey you’ll be the first to do it to my knowledge!

Might need to find a carb setup for boost. Because the factory carb just wasn't meant for what your asking of it.

Don’t give up on it. Need to try a smaller spark plug gap. I bet when it gets to a higher boost it’s blowing the spark out.

Might check out a few grind hard plumbing videos I know they have successfully put turbos on a couple atv and dirtbike engines.

Try a 04'/05' 450r carb made mine scream with all other stuff i did but thinkin with your setup OMG THROTTLE RESPONSE would be crazy Also Sigma6 makes a complete jet kit for turbo setup an much more Only given sum ideas keep up the Awesome work and vids!✌🤘🖖

New carb, a head spacer to lower compression and run positive pressure to the vent on gas tank. Also make sure youre using the right heat range on yor plug for the turbo

A buddy turbocharged his harley and he was having same troubles but later figured it out and talk about seeing the face on guys faces when a rocket Flys by and they look and see he is right there beside them is funny

There's gotta be a local tuner shop around. Just a smaller version of what they do. I bet they'd be glad to help on a unique project.

It has a vacuum slide in the carburetor and with you putting booth reference into all the ports on the carburetor it is pushing the slide close

I wonder if a smart carb or lectron would better react to the sudden increase in fuel demand when the boost hits better than a conventional carb

Your going to have to put the carb on intake of turbo. That carb just won’t work blow through. Get a good gravity short ram into the turbo with carb and try to get turbo as close as possible to head. You got this. This is just my recommendation

joe id recommend the wastegate spring may be only 5 lb and with turbos u have to knock timing usually unless its self learning but why i say waste gate spring is because itll make over a certain boost then cut the excess out its what its for and itd limit boost

You need to replace the needle and seat with a set up for a fuel pump. The hole in the seat should be smaller because it provides more PSI at the sealing surface of the needle.

You need a wide band o2 sensor and data logger to see what the fuel ratio is doing under load

You could try a Keihin FCR 39mm or 41mm carburetor. The carburetor you are using is a diaphragm carburetor and when I charge the turbo it makes the carburetor plunger go to the maximum and you lose control.

That exhaust flange cut it off😂😂😂

It might want to go, but it just isn't. Lol! Good luck bro!

A carb with a diaphragm slide would probably work better in this scenario. It automatically opens the slide depending on airflow into the carb giving you better fuel ratio control. Also gap the plug tighter 👍👍👍👍👍👍

Tighten up your sparkplug gap a lot just so you can barely have a small gap, it sounds like when your are starting to build boost the pressure from the turbo is blowing out the fire on the spark plug, had the same problem with a Chevy 6.0 built motor with twin turbos and that was the problem, it may or may not fix problem but that is what it sounds like, Give it a try and good luck and I hope this helps.

question. since u add turbo more psi fuel and oil pump along with top end rebuild wouldnt some type of tune or bigger engine or something to help compensate for the added boost?

Maybe look into getting a mini squirt that way you can adjust the ignition timing when under boost also try regulating boost pressure to 3 pounds that way it can spool lower in the rpm range and hold a steady boost pressure without lagging so long before it comes on

Have you port polished the valves or upgraded your valves or anything to stage three such as your cam? Not sure if that'll work or what you have done to the quad hopefully that helps or gives a idea!

I know with my water regulator, you have to turn it in (clockwise) to reduce the pressure. Try that.

you need a boost cut off gauge that's adjustable so can set to like 5 psi so she don't pop again unless you build that motor

You got this man, dont give up. I'm sure you'll get that thing dialed

I think I know the problem, you tried to make a time machine out of a Delorian. LOL. Man I was rooting for you on this one but I was a little skeptical. Please keep making great content.

dont give up

The accelerator pump under the black throttle plate is leaking. When you hit the throttle, the accelerator arm is actuated by the throttle mechanism. Take off the black plate on the right side of the carb and watch the fuel flow. Pops

I really want to see this thing run.

I don't know how your settup is but you need to have your float bowl vent tube plumbed in to the pressure side so that the float bowl stays the same pressure as the boost

I think you should shorten your pipes. Think of a car turbo system. Usually turbo sits right off the exhaust manifold. very close to the engine. Think of air flow. The exhaust has a long way to travel on the 400. Just my opinion. Shorten the airflow. Maybe that will give you better spool.

Check to see how well waste gate puck is sealing at exhaust housing, you may need to throw a helper spring on the waste gate actuator to keep it sealed, if tension seems to be lite. Secondly see how much material there is where puck seals up to the exhaust housing, if there’s seems to be a lot, scribe it and port it out to where there’s just enough material that it will seal, I’ve seen that cause turbo surge Numerous times. Good luck...

You need a wideband o2 sensor and tune afr for 12.5 to 1 and do plug chops and adjust from there.

Turbos only really make boost under load, that's why it free revs no problem. The easiest solution for you may be an auxiliary fuel injector in the intake made to come on when boost comes in. You definitely need way fatter main jet and make sure the fuel bowl isn't running dry as well for the current set up

Cool 😎 next you should turbo a busa 😏

When you picked up that package I thought you were going to say we are going to add some twizzlers.

I had a 1988 Ford Thunderbird turbo coupe when I did a tuneup on it I put Cheaper spark plugs in it when it would hit 5 pounds of boost it ran fine anything over that it would cut out you might try something as simple as a more expensive spark plug

Have you tried running the bowl vent to the boost signal? The bowl has to be the same pressure as the manifold pressure or it won't draw fuel under boost

Weld a flange onto the base of a big slip on pipe, and bolt it straight to the turbo exhaust housing for simple center exhaust

Did you put a little extra gap in the piston rings for the extra heat from being turbo'd? Also is that a rubber coupler going from the header to the 90 into the turbo? No bueno

Hey man. From what I see and can hear the turbo needs too be closer too the engine or your piping for the turbo needs too be smaller. There is too much space and that engine can not move enough air.. on cars there is 8 cylinders or 6 or 4 that are pushing air for the turbo..on cars you could basically put the turbo anywhere and it will work. I'd say try too get the turbo closer too the engine. Good luck man I love your videos keep up the good work.

Turbos and carbs together suck to tune you’ll get it there eventually

Is there a return pipe from the carb to the tank? Reminds me of a problem i had before where the fuel return pipe was blocked on a yamaha Fazer. The return pipe used to relieve the pressure into the fuel filler cap and back into the tank. Might be way off but just a thought, love your vids anyway 👍

Kyle from boosted boyz turboed a go kart and they had issues but finally got it right .ya might want to watch there go-kart vid I know they moved the turbo to a different spot and got it to work

I wonder if a flat slide carburetor would work? Maybe the butterfly carb doesn’t like the boost.

The backfiring on decel is lean. Go up to a 180 or 185 jet and if possible install an efi kit

Those carbs are meant to work with vacuum, if you put pressure in there(boost) you will have serious fuel issues. You need a blow-through carb for boost applications. Would of been far simpler to boost an EFI(fuel injected) quad and add a tunable ECU to adjust fuel tables and ignition with software on a laptop... makes things so much easier.

Only seen this latest video but just one bit of advice, if you don't pressurize the carburetor bowl so it matches the boost coming into the carburetor how do you expect it to draw fuel.? If you're intake track is pressurized it's going to blow into the carburetor instead of drawing fuel out. Just my two cents

You really should switch out the oil feed system to an external oil tank, oil cooler and like an electric oil pump. Your oil flow is not sufficient enough and not cool enough for the addition of the turbo since you're not running coolant. Also, trying to turbocharge a single cylinder 4-stroke is going to be quite a pain considering the exhaust stroke and the intake stroke. Remember, the intake valve is closed when the exhaust valve is open, so trying to force more air into the single cylinder while it's trying to exhaust isn't going to "make boost" like you want it to. Do NOT expect the whoosh noises you're desperately trying to get. In this application, all you're really doing is making sure the forced induction is there for when the intake valve is open. For what you're trying to achieve, you should put the 400ex back to stock exhaust, intake, and fueling and get yourself at the very least a 2-cylinder, if not a 4-cylinder or you're going to keep blowing motors up trying to get the results you want, instead of getting the results you have.

Did you try tightening the plug gap if it's making 5 pounds then cutting out maybe it's blowing the spark out

Needs a pull through serup and it'll be a beast!!

Sounds like it’s blowing the spark out under boost. Should try a anti fouling adapter to help shield the spark.

Seems like a calibrated mass air flow meter to suit the extra fuel needs , would probably work better then what ur doin

Have you tried changing the clip position on the needle in the slide ?

Yo, u can't quit out on this bro. After all the time invested so far, and knowledge uve gained, u may as well see it through. Esp for all us viewers that want to try this, u could help pave the way so we can get an idea what we need to do. There's alot of turbo gurus in here that are mentioning stuff thag u haven't tried yet so just consider it bro. That would be sick to be seen through. Ur almost there. Put a lectron carb. No jetting needed

If you have a stock 400ex carb can you do a video on how to rebuild/clean it

What about reducing the spark plug gap?

Possibly check the spark plug gap and possibly change the heat range of the spark plug

Is that surging being caused by un-controlled boost? Ie: un-controlled boost upsetting fuel mixtures under load?.. try boost controller/boost tee and keep it at six or seven pounds boost and tune fuel around that..

You need a plenum for the boost tube so there’s a chance for a gulp of air basically a empty box welded on the tube so it’s not just pulses of air every stroke. Your welcome have a nice day