Turbo Mountain Max

yamaha3 said:

I honestly dont think that the turbo that i am using is too small.

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i tried to be polite to start, but honestly. your gonna nuke the motor in about 30 seconds with that turbo.. even if its tuned right. its WAY to small.. you cannot put a t04exhaust side on a 2 stroke any bigger then a 440 unless you want to burn it up from WAY to much backpressure.

do like 1 pass at your house so you dont have to pull it home and waste your friends time when it burns down as soon as you start riding it.

and yes, i have built/ been around more then a few homebuilt turbo 2 strokes.. theres a lot of things you can get away with and have one that runs, not well, just runs, and your already heading the wrong direction, just trying to keep you from wasting your time..

How is this ever going to work with no pipe and no expansion chamber? I also agree that turbo is much to small for a triple.

I think you can make it work, I've heard of quite reliable turbo 2 strokes that were home-made and as long as their set up right they ran fine. It will need a pipe before the turbo, a single will spool faster but triples will make more power, but spool slower because of some heat loss. Don't use too small of an exhaust housing on a case reed 2 stroke since they can't handle much back pressure. I'm working on a mountain max turbo right now, I was told that any turbo that will support 300 Hp on a 2 liter car engine should be big enough. It's best to have a ball bearing turbo too so you don't have the oiling problems common with journal bearing ones and they spool quicker too. I'm thinking a Garrett 2871 should be enough with triple pipes but I don't want to spend more on a turbo than I spent on the sled either. T25's are easy to come by, but again the exhaust side is said to be too small on anything bigger than a 700 twin. You'll need a boost referenced fuel press. regulator so fuel pressure rises proportionate to boost press. and doesn't flood at idle. Let us know how it goes.

MM

chris, give me a call i have a couple gt2554. That 13g is way too small for that motor, also i would get a stock pipe, it may work without but not very well. if you dont have a pipe i have a few. 591-9699

mm

I havent heard anyone say it will work with straight pipes?? It will NOT work right the way it is now. A larger turbo needs to be at the end of the stock pipe.

mm

I think a 2860,2871 or 16g would be ideal for this motor

Ok, I just saw this for the first time, so here are my thoughts.

I see it is not an areocharger turbo, so you are one up already. I do not know about the size of that turbo, but the yamaha 700 sx motors have a really short stroke, so there really is not as much forced combustion as many think. That was my problem, too little air and too much inbetween the the turbo and the pipe.
Move the thing at the end of a stock pipe, then just run a strait pipe out for exaust(sounds frikkin awesome!)
Get fuel jets, you will need them.
Use stock reeds. Anything else will blow out(found that one out the hard way)
Tune, tune tune!
If you cant get rid of the low end bog, do not try to fix it with clutching, get a little shot of noz, that was easier.

Like dkidoo guy whateverhisname was said, try it close to home first, saves on buddy tow time.

Dont know alot about turbos but i love the motorcycle seat set up! i wanna do it can you give me a quick breakdown on how and what you used to mount it and how well it works? thanks

Grenade!

That Turbo cannot be mounted there! Ski-dooin It is right, that Turbo is to restrictive and will cause excessive amounts of heat!

i turboed my powder extreme 600 trippple. here is my sugjestion. take that turbo off and put it on ebay!!! take all that mumbo jumbo off aswell and do exactly as i say! first go on ebay and look for mits 16g turbo or something with a .86a/r exhaust housing mabe even a t4. triples put out way more than a twin. i used a t3 and it worked ok. 2nd get a oil pump as no you cant just block it of lol. 3rd build yourself a air plenium as you dont need a intercooler(unless you want one) then go get a fuel pump,rising rate fuel pressure reg.,power jets,bov,wastegate(unless the turbo you get already has one),aluminum piping,couplers,t's for fuel line(get the aluminum ones),heat wrap for exhaust,battery with reticifer,air/fuel sensor(unless you are a god of tuning which i am not lol),clamp on filter,you should not spend more than $120 on a turbo off ebay. fuel pump will run at 35$,fuel reg. 50$,i used thunder product power jets which were 75$ a peice but you can get mikuni power jets for 30$,bov 20$,get piping from a local hardware store cuz if you buy it on line it can get spendy! expect like 10$ for piping,couplers are like 3$ a peice,heat wrap is like 50$ for 2 in and like 50ft,not sure on battery and such,get a/f sensor and guage kit from autozone for like 20$..... i ran 5psi on my sled max because it is gasket head not o ring. you need to put on stock pipe and wrap it,then put turbo off it. i dumped my exhaust out the front of belly pan by the a arms to reduce sno build up.triples have no probalem spooling a big turbo. if your looking to only run 7 psi you could do it on stock internals fairly reliable to but run premium fuel only. if i didnt just sell my 600 i would post some pics of the beat. i put a 162 under it,turbo,powder pros,fox floats,billit a-arms,m7 mtn bars with 3 in riser so they were like 10in high. that sled could make a new m8 wish it was never built. i tightend the limiter straps pretty tight but i still found the skis tward the sky.a good running turbo 2 stroke is a great sled but when the motor goes byby it literally goes byby. i hope i helped,but seriously dont destroy a great sled for no reason. do it right and have the king of the hill!!!

also if i were you i would get a set of tripple pipes to put out more exhaust.

So how's this project going? give us an update! I'm interested in seeing how it runs.

just wondering how the turbo is comming can't wait to see it run

I have all the parts you need in stock to build this animal.

You are going to need to use the stock pipe. At least a 16 g or 2860 I like the ball bearing turbo's because you do not need as much oil supply. Never have found a good oil pump for a jornl bearing that has some life to it. Powers jets are a must. Start with stock reeds. You have to run reeds. Jet the carbs down because they become more efficient under boost. Riser fuel reg. Get silicone charge couplers. They don't get hard and brittle.

I promise us guys that do these things for a living have been there done that. We will not lead you astray. Listen and learn will save you a ton of time, money, and head ache.

When you get it done you will have a perma grin :face-icon-small-hap:biggrin1::bounce:

OP hasn't posted in 2 months. We can only assume that he tried to run his sled as is, burned it down within minutes of unloading and he is sitting beside a trail somewhere....Right? I thought so.

I'm still looking to turbo mine, anyone have thoughts on what size of turbo would work? I'm thinking Garrett GT2871r since that's what most 2-stroke Polaris 700/800's and others are using. I'm running a single pipe because of clearance issues, but if it works good, I may attempt the triples with a turbo. Right now I have a T3/T4 journal bearing turbo I wouldn't mind trying, but hear of constant lube issues when running journal bearing turbo's. Any info helps.:face-icon-small-hap