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bzerk
08-31-2008, 09:36 PM
what kind of turbo can you put on a tri-z 250

Billy Golightly
08-31-2008, 09:38 PM
This is a really complicated subject. If your serious about it, do a search on amazon.com for "motorcycle turbo" and buy corky bell book and the other one thats got the drag bike on the front. You'll need to learn and read a lot.

SCEADU
08-31-2008, 09:42 PM
Can a 2-stroke have a turbo? I know that detroit makes a 2 stroke diesel but I thought they had to be super charged becuse the turbo would mess with the way a 2 stroke operates. Learn sumtin new everyday.

300rman
08-31-2008, 09:50 PM
yeah, this isnt something commonly done. and i cant see this helping much in a 2 stroke because of how they run. the pressure shot into the crankcase would be pressure the piston has to overcome to come down, and the extra pressure on the reeds could be bad, and since the intake port closes before the exhaust port, i dont see how the turbo could further pressurize the combustion chamber anyway, as all the extra pressure will rush out the exhaust port before the port closes.

feel free to chime in and correct me if im wrong?

seems like it would be cheaper for you to pre-order a tri-Z 330 kit,
can be pre-ordered here http://www.planettrike.com/showthread.php?t=357

one run of these has already been made, and they have proven to be reliable and POWERFUL. ill bet with a good port job, reeds, bigger carb it would be all the power you would ever need.

bzerk
08-31-2008, 09:58 PM
i already have the 330 kit

Billy Golightly
08-31-2008, 10:45 PM
They can be built and put on 2 strokes. Theres a metric *Edited**Edited**Edited**Edited*-ton of tuning variables though, and you have to select the right type of turbo, the right type of plumbing (blow through, draw through styles just for a beginning example). You need to learn how to read compressor maps as the very first step so that you get a turbo the right size and out put. Decide whether you want to use a common oil float type where you have to build an auxillary oil tank and oil pressure pump/system or try and locate a self lubricating one (extremely hard to find, extremely expensive) I've done hundreds of hours of research on the subject and could more then likely build a functioning setup if i had the time and money to do it...but only because I'm a pretty good fab guy and that I have spent so much time and effort looking into it. Don't even attempt it or try it until you've done enough research to have the entire thing planned from start to finish with every single part necessary listed and every probable issue sorted and solved.

Daddio
08-31-2008, 11:13 PM
Can a 2-stroke have a turbo? I know that detroit makes a 2 stroke diesel but I thought they had to be super charged becuse the turbo would mess with the way a 2 stroke operates. Learn sumtin new everyday.

I spent four years operating a Terex TS24b Scraper and it was powered by two Detroit diesels. It had a V12 in the front and a V6 in the rear. They had turbochargers feeding the superchargers. Hard core stuff there buddy. :naughty:
Here is a link to one with some cool pictures.
http://www.machinerytrader.com/listings/detail.aspx?ohid=6054124

SCEADU
08-31-2008, 11:56 PM
I ran a Michigan B75 with the above said 2 stroke diesel for a few years and I remember the first day on the thing . The boss comes up to me and says "Son you gotta run it like you stole it". When the engine went down I helped to rebuild it but everything on it was Greek to me. Just did what he told me to do. When I asked where the turbo was I thought he said that 2 strokes are blown not turbo. Could be wrong though that was 20 years back.

bzerk
09-01-2008, 12:28 AM
do you think it will add much hp

300rman
09-01-2008, 01:53 AM
They can be built and put on 2 strokes.

i can see where most of the tunign would come into play, and all that fun stuff. but explain to me this.

How can the combustion chamber become further pressurized when the exhaust port is open longer than the intake port? how does the air not simply blow through the cylinder into the pipe? i mean, obviously ALL of it wont, but i cant see more than a 2-3 PSI boost MAX no matter how hard you crank the turbo.

seems to me a 2mm greater stroke, with a higher compression domed head would be cheaper and just as, if not more, effective.




i already have the 330 kit
than get it ported by a reputable company. PR Racing does excellent work, and they have made many monster engines in their day.
higher compression could also be another route?
Vforce reeds?

i imagine you also have the aftermarket intake that Sprock Racing makes, and the other goodies he has available.

sbjones73
09-01-2008, 04:06 AM
one of my older friends still drags a snowmobile that is 2 stroke that is turbo'd. he says it was a pain to get it "right" but man that thing rips like you wouldn't believe.

and for a note here. detroit made several 2 stroke engines that were turbo charged. like the 71 series engine, they were turbo's. then came the 92 series that ran turbo's and blowers ( i am really only talking 6v and 8v engine here, no four cylinders or v12's)

Billy Golightly
09-01-2008, 07:03 AM
i can see where most of the tunign would come into play, and all that fun stuff. but explain to me this.

How can the combustion chamber become further pressurized when the exhaust port is open longer than the intake port? how does the air not simply blow through the cylinder into the pipe? i mean, obviously ALL of it wont, but i cant see more than a 2-3 PSI boost MAX no matter how hard you crank the turbo.

seems to me a 2mm greater stroke, with a higher compression domed head would be cheaper and just as, if not more, effective.




than get it ported by a reputable company. PR Racing does excellent work, and they have made many monster engines in their day.
higher compression could also be another route?
Vforce reeds?

i imagine you also have the aftermarket intake that Sprock Racing makes, and the other goodies he has available.



I don't have enough time (headed to work in like 5 min) to explain it really in depthly, but more or less the turbo goes after the pipe, and then the pipe harmonics and pressure waves still work as they did before. Hell you get +/- 7psi pressure changes in a good expansion chamber just with a normally aspirated engine. And the cylinder never actually starts to pressurize on the up stroke until the exhaust port is closed anyways.

The turbo if its dialed in and has an efficient compressor ratio that matches the engine will do like 45-50% gain depending on the boost pressure, I think those percentages would be based on an 8-10psi # which is probably about all your going to get with the engines we're talking about before you have to get really creative with the crank seals. So if you've got a 60hp motor your looking at 90 or close to it.

fabiodriven
09-01-2008, 10:06 AM
one of my older friends still drags a snowmobile that is 2 stroke that is turbo'd. he says it was a pain to get it "right" but man that thing rips like you wouldn't believe.

and for a note here. detroit made several 2 stroke engines that were turbo charged. like the 71 series engine, they were turbo's. then came the 92 series that ran turbo's and blowers ( i am really only talking 6v and 8v engine here, no four cylinders or v12's)

As for the 3-53 and 4-53 Deroits- I had a 3-53 with just a blower, I think that's the only way they came. But the 4-53 you could get with a blower and a turbo, or just a blower.

cheaptecate
09-01-2008, 11:52 AM
Two stroke diesels are not like two stroke gas motors. The diesels still have valves on the exhaust. Only the intake side of the motor is like a gas two stroke. This may be why the two stroke diesel works so well with the turbo. A diesel, 4 stroke of 2, is usually a dog without some boost.

Daddio
09-01-2008, 01:37 PM
Two stroke diesels are not like two stroke gas motors. The diesels still have valves on the exhaust. Only the intake side of the motor is like a gas two stroke. This may be why the two stroke diesel works so well with the turbo. A diesel, 4 stroke of 2, is usually a dog without some boost.

Actually I believe that they,2stroke diesels, have to have some kind of boost in order to run properly. Check link below. I think we are really getting off topic here.
http://auto.howstuffworks.com/diesel-two-stroke1.htm

300rman
09-01-2008, 03:16 PM
I think we are really getting off topic here.

http://www.threadbombing.com/data/media/4/derailed.jpg (http://www.threadbombing.com/details.php?image_id=2622)
:lol: :lol: :lol: :lol: :lol: :lol: :eek: :naughty: :D :cool: :welcome: :TrikesOwn
J/K with ya man, just seemed like a good time to bring out that pic :D


i am still not quite understanding how the pressure on the intake side pressurizes the combustion chamber if the exhaust port is still open.
only thing i can think of is that it happens so fast, there isnt enough time for the pressure to bleed out?

fabiodriven
09-01-2008, 03:48 PM
I think you pretty much have the concept, 300. When the port at the base of the cylender is open, I think it simultaniously pushes the exhaust gas out and the fresh charge in.

Andrew_250R
09-01-2008, 06:31 PM
If I remember correctly from college the detroits had superchargers on them to aid in starting. Without the supercharger they couldn't build enough compression to start.

Andrew_250R
09-01-2008, 06:37 PM
Actually I believe that they,2stroke diesels, have to have some kind of boost in order to run properly. Check link below. I think we are really getting off topic here.
http://auto.howstuffworks.com/diesel-two-stroke1.htm

Kind of ironic that in that link they say that the diesel two stroke is not plagued with the environment issues that a gas two stroke is. Considering the diesel stroke was discontinued because it couldn't meet (or it cost too much to meet them) emission standards.

Billy Golightly
09-01-2008, 08:57 PM
http://www.threadbombing.com/data/media/4/derailed.jpg (http://www.threadbombing.com/details.php?image_id=2622)
:lol: :lol: :lol: :lol: :lol: :lol: :eek: :naughty: :D :cool: :welcome: :TrikesOwn
J/K with ya man, just seemed like a good time to bring out that pic :D


i am still not quite understanding how the pressure on the intake side pressurizes the combustion chamber if the exhaust port is still open.
only thing i can think of is that it happens so fast, there isnt enough time for the pressure to bleed out?



Don't you understand the general principle of a 2 stroke engine? It doesn't matter if the incoming charge goes out the exhaust port, because it gets sucked/pushed back in thanks to the pipe right as it (exhaust port) closes and it gets trapped back inside the combustion chamber where its ignited and burnt.

Your thinking of this as a static, straight through hole from the intake to the exhaust, and its not.

Black86tri-z
09-01-2008, 11:38 PM
join this forum im a member here 2 http://www.theturboforums.com/smf/index.php

300rman
09-01-2008, 11:52 PM
Don't you understand the general principle of a 2 stroke engine? It doesn't matter if the incoming charge goes out the exhaust port, because it gets sucked/pushed back in thanks to the pipe right as it (exhaust port) closes and it gets trapped back inside the combustion chamber where its ignited and burnt.

Your thinking of this as a static, straight through hole from the intake to the exhaust, and its not.

i perfectly understand how a 2 stroke engine works. but when the piston goes down, it only pushes into the combustion chamber the exact right amount of air to fill the cylinder. pushing more in would seemingly overcome that back wave.

it seems like there would be a certain threshold that more boost wouldnt equal more combustion chamber PSI due to the pressure overcoming the back charge.

hondawasaki
09-02-2008, 12:58 AM
A two stroke, just like a four stroke builds power from a higher intake charge. Think of it like this, I live at high altitude, if I drive down to sea level with my two stroke it makes more power with slight boost in intake pressure, natures turbo.

What you are talking about 300R is the scavenging effects of the expansion chamber, like billy noted it will have to be tuned (it will be a much bigger cahmber as the combustion gasses will be higher in volume) , for the higher intake pressure. I think Billy is right the weak link for turbo'ing a 2-stroke would probably be the crank seals, I'm sure there are seal makers that could supply a higher lip tension to compensate, but again it will all depend on your boost pressure.

when I was at CPI they had 2 sleds getting a turbo kits, the interesting thing to me was that the carburetor was not being pressurized, the carbs were before the turbo. Billy?

Billy Golightly
09-02-2008, 08:55 PM
That'd be called a draw through setup (and since I'm home from work, I have adequate time to explain now :))

The draw through setups are the easiest to install and mechanically plumb/construct into the motor. But they are by far, the hardest to tune and dial in. This is mainly because the fuel mixture does not stay atomized very well because of the long distances and also having to travel past the turbo blade. You'd think that'd be a great mixer, but it actually acts as a separator and there are actually reports of some draw through setups having a PUDDLE of fuel in the bottom of the turbo housing from it separating so much. And depending on engine speed, you end up with huge spikes of lean spots from the fuel seperating, and huge spikes of richness at other speeds. Most of the draw through setups I've seen or heard of being built are sooner or later (Normally sooner) re-plumbed and designed and made into blow through deals.

The blow throughs are harder to build, but work better. The first thing most people think about is, how is a carb going to work with a different atmospheric pressure being forced into the back of it , when a carb is built and designed to operate on a vacuum that will pull the fuel up past the jets in the carb. I had this same question, and I believe it was Joe Haile's book about super/turbo/air induction and nitrous on motorcycles (The one I mentioned before) where he suggests the solution is to simply connect the carb vents to the the suction end for the turbo. That changes the pressure in the bowl and makes it where the carb will work on its suggested and designed principle of working off of a vacuum. Atleast I think thats where they went, I don't have my book here handy to reference since I'm not at home.

The next major issue with a blow through setup is making the carburetor 8-10psi air tight. Some guys build/weld complete aluminum boxes around the carb, and don't even have the throttle cable through directly to the carb itself, but instead connect to a rocker arm of some type on the outside, which turns a shaft riding in a sealed bearing that has another arm on the INSIDE of the box, which actually operates the slide up and down.

And then, you have to make provisions for a BOV. Blow off valve. Cause if your got the turbo spinned up, and chop the throttle closed, bad things will happen :lol:.

And with whatever setup, if its a normal oil bathe/float setup style turbo you have to make an oil tank, lines, and an oil pump to pressurize the turbo to its necessary amount to make sure the shaft in it rides on the oil that it needs. There are as I mentioned, self lubricating turbos that don't need external oiling setups. A popular brand was "Aerocharger" which was sold by numerous places and businesses. Hi-per, that makes the carbon fiber ATV wheels was one of many places that handled these when they first came out about 8 years ago. The company folded about 2-3 years after it opened though, and they are extremely hard to find now. IF you can find one, expect to pay like 3-4gs just for the little turbo itself. The sled guys and the drag racers snap em up like crazy.

And then, for the motor itself.

All the gasket surfaces would need to be thought of. I almost completely abandoned the idea/quest myself when I thought of the fact that the center cases would have to be o-ringed to hold the pressure, which would be like near impossible to do. I did some searching though, and a few places, like McMaster Carr, have a selection of very high quality rubber gasket material (that is also very expensive) that could be cut and used. Some of it supposedly has pressure ratings up to like 50psi, which would be really interesting to try even just in a regular motor. Infinitely re-usable gaskets would be awfully handy. Its possible gasket makers like Cometic and others already have some of this material, and if they don't, its more then likely possible to get a hold of the material itself from a third party and have them cut from it for you. Crank seals, I never really got that far, other then I heard of some tests a few people did with 250r motors and were managing to get them to leak after the crankcase was pressured up to about 25lbs. Never did it myself to find out what I could get though. The head will probably need to be girdled, and you'll need some REALLY good grade cyl and head studs/nuts as well.

And I'm sure theres even more stuff that I haven't thought or or learned about. Its really not just bolt on a turbo and off you guy...theres an awful lot of thought and work involved.

hondawasaki
09-03-2008, 01:53 AM
Thanks for the explanation Billy, all the turbo setups I have seen on carbureted engines have had boxes around the carbs, so to see one drawing air through was foreign to me.

If the 250R's seal failure point is 25 lbs, you would think 15 lbs would be a safe running point. Good lord 15 lbs boost on a 250R, makes my skin tingle! I'm sure there are places that have done this kind of thing before, and know exactly what needs to be done.

I can't imagine shops o-ringing the cases on these 3-4 cyl sleds, so the silicone must have a pretty good pressure threshold.

Realistically, this sounds like a humongous bomb waiting to go off! talk about a money pit LOL......

Daddio
09-03-2008, 10:48 PM
A lot of the guys that we see at the dirt drags run nitrous. They say its the poor mans supercharger. The only restrictions on the class that 1upfront races in at dirt country is 300cc or less 2stroke and no nitrous.

dogger
09-25-2008, 04:08 PM
hey billy should I get you back into thinking about turboing a 2 stroke? I've done a far amount of research myself and I think I got the solution to the seal's. I located a main supplier for the auto industry that makes and stocks off the wall type seals'. just so happens they make a hydrolic seal that would fit the 250r and should hold the pressure quite fine. the gasket though might be a problem and they might not. the crankcase doesn't see the same pressure that the cylinder does which for sure I would oring. if it becomes a problem I could source out a mls style gasket which would hold the pressure find. also the carb issue has been solved more ways then I could count but a method one of my buddies has used many times was to pressureize the bowl a little high then the intake charge which then makes a vacuum effect in the carb. also you'll then need a fuel pump and regulator. I've considered doing a 250r turbo but have not done one yet I'm working on designing one right now for my ktm 625 with the hopes of getting around 85hp out of it.

btw to the remark on how would you pressurize a two stroke with out it bleeding off. the part your missing is you not only have pressure build up in the intake but the exhaust now builds pressure to before the turbo because you have a restriction. so any point after the intake housing or before the exhaust housing is going to have a pressure build up in it. and turboing a two stroke is nothing new. in the 30's their was some race teams and bike manufacters that were turboing their two strokes to see what could be done with it and some worked very well

boosted96cobra
10-09-2008, 02:48 AM
I have been thinking of this also. I was wondering if the oiling of the turbo could be taken care of by a small vacum pump like the odyessy and the tri-z use for a fuel pump? That way you could have a small res for the oil, use the pump to pump oil up to the turbo and have it drain back into the res, and have one more hose to the vac side of the turbo.

I also had a long campfire talk at The Mosh with one of the guys from cpi that made hondawasaki 500 pipe, and he said when they do a blow through carb setup, one of the things that happens is it pressurises the bowl and pushes the fuel out of the overflow, so they ran a hose off of that to a powerjet (dial a jet) that is placed in the intake for extra fuel and tuning ability.

lonestarion
11-09-2008, 06:36 PM
the turbo from th latest model mercury capri is sall enuff to work on a bike with low cc's. i dont remember who makes the turbo IHI or mitsubishi, of which are great turbos.

300rman
11-14-2008, 12:24 AM
hey billy should I get you back into thinking about turboing a 2 stroke? I've done a far amount of research myself and I think I got the solution to the seal's. I located a main supplier for the auto industry that makes and stocks off the wall type seals'. just so happens they make a hydrolic seal that would fit the 250r and should hold the pressure quite fine. the gasket though might be a problem and they might not. the crankcase doesn't see the same pressure that the cylinder does which for sure I would oring. if it becomes a problem I could source out a mls style gasket which would hold the pressure find. also the carb issue has been solved more ways then I could count but a method one of my buddies has used many times was to pressureize the bowl a little high then the intake charge which then makes a vacuum effect in the carb. also you'll then need a fuel pump and regulator. I've considered doing a 250r turbo but have not done one yet I'm working on designing one right now for my ktm 625 with the hopes of getting around 85hp out of it.

btw to the remark on how would you pressurize a two stroke with out it bleeding off. the part your missing is you not only have pressure build up in the intake but the exhaust now builds pressure to before the turbo because you have a restriction. so any point after the intake housing or before the exhaust housing is going to have a pressure build up in it. and turboing a two stroke is nothing new. in the 30's their was some race teams and bike manufacters that were turboing their two strokes to see what could be done with it and some worked very well

while this is all very interesting, it would be a waste to turbo a 250R. the SaberTooth top end makes about a hundred horse, and it is notorious for killing 250r trannies. i imagine after turboing a 330 kit on a 250R, your still going to have trans issues. and turboing the 250 top end seems moot point because for MUCH less effort, you can have a 330 or 350 kit.
i guess if you have piles of money, and want to be different, its a great idea, but i'd rather turbo a Shee motor, those mottom ends are known to take some serious ponypower!