how to turbocharged 2 stroke ????

warrenp · October 4th, 2006, 03:56 PM

any one have info on turbocharging a 2 stroke like a snowmobile.
i have a small 340 Polaris and a ihi RBH5 i would like to utilize.

i think they would make a good match.

also I'm trying to be cheep on this.
so what could i use as a oil scavenge pump?

i found pumps but they want almost $200 for one.
seems like there must be some alternative

a6t8vw · October 5th, 2006, 02:34 AM

ive seen only 1 turbo 2-stroke in my life, it was a 500cc banshee out at glamis CA. The owner didnt seem to get it to run that great... Sounded SUPER nasty and had a very narrow power band...

secondly a 2-stroke needs the Expansion chamber to extract the gas's from the motor.. and a turbo would disrupt that theroy all together...

im not saying it cant be done, but it woudlnt run that great.. for one thing the piston on the up stroke draws air in thrugh the REED VALVE which is a one way valve. When the piston is going down the valve is closed and the air/fuel under the piston and crankcase is pressurized forceing the air up the transferports and back on top of the piston.... so if the turbo was spooled produceing boost it would open the reed valve ALL THE TIME when the piston is creating pressure on the down stroke to close it so basicly the turbo would FIGHT with motor. and haha just thought of that ^^

your best bet to make power with a 2-stroke is porting and a high compression head... and a high octane fuel to back up the high compression

andy

dr_hunt · October 5th, 2006, 04:27 AM

Considering the detroit 2 stroke diesel engines work well, I son't see anything that makes it so that it won't work. Detroits have a large round expansion chamber and open exhaust and are blown and turbo'd. Ditch the reed valve setup as it's no longer needed. Would be interesting to see how it worked.

veritech-z · October 5th, 2006, 07:29 AM

I'd actually heard that it can't be done, If you do find a way, be sure and let us know...It seems like all the makers of outdoor power equipment would rather turbo/supercharge 4 stroke enignes...seeing as how they have no problem doing that, I would HAVE to think that if it were feasable, SOMEBODY would have released an OEM turbo quad/jet-ski/snowmobile by now...

warrenp · October 5th, 2006, 08:26 AM

whe ni did a serch i found a guy that turboed a vespa seems to work ok.
but there wasn't any info on it.

believe me i have made up my mind. i'm puttin a tubo on it!
where's the expansion chamber located on a detroit????

detroit 2 stroks have to have a blower or i do not htink they wouldn't run or at least not properly.

also along with my serches some one made a kit for a banshee at one time.
i don't think it's made any more

veritech-z · October 5th, 2006, 08:34 AM

Vespas are 2-stroke? I thought they were 4 cycle.

SHO-Z · October 5th, 2006, 10:20 AM

Two strokes require the gas/oil mixture going through the lower end for lubrication. The crank seals are not designed for a whole lot of pressure. If you really want to get some more HP out of the machine install an expansion chamber installed for the engine, match the ports between the lower end cases and the barrel. If it has a chrome lined barrel you cannot do much with the ports in the cylinder area. Another old trick is the stuff the crank. Some cranks have holes in them, we used to fill these holes with magnesium and get some added HP. If the engine has reed valves in the intake get some high performance ones that are a little more flexible.

Hopping up a 2 stroke is a whole new world.

To put a turbo you would have to have some type of electric oil pump to lube the turbo. If you could turbo a 2 stroke and make it run Saab would have had them on there 2 stroke rally cars back in the 50 and 60s
.

Sam280Z · October 5th, 2006, 12:25 PM

There is a whole 4 page chapter on it in this book:

http://www.amazon.com/Turbochargers-...e=UTF8&s=books

a6t8vw · October 5th, 2006, 01:54 PM

heres a cool turbo quad useing 1300cc streetbike motor 4-stroke
http://videos.streetfire.net/categor...DF995CEDC9.htm
i actually found some turbo-2 stoke stuff
this guy builds em
http://www.trickracing1.com/home.html scroll down to turbo stuff

warrenp · October 5th, 2006, 02:03 PM

Quote:

Originally Posted by veritech-z

Vespas are 2-stroke? I thought they were 4 cycle.

http://video.google.com/videoplay?do...297703&q=turbo
it's an older vespa that might be why

warrenp · October 5th, 2006, 02:07 PM

Quote:

Originally Posted by SHO-Z

Two strokes require the gas/oil mixture going through the lower end for lubrication. The crank seals are not designed for a whole lot of pressure. If you really want to get some more HP out of the machine install an expansion chamber installed for the engine, match the ports between the lower end cases and the barrel. If it has a chrome lined barrel you cannot do much with the ports in the cylinder area. Another old trick is the stuff the crank. Some cranks have holes in them, we used to fill these holes with magnesium and get some added HP. If the engine has reed valves in the intake get some high performance ones that are a little more flexible.

Hopping up a 2 stroke is a whole new world.

To put a turbo you would have to have some type of electric oil pump to lube the turbo. If you could turbo a 2 stroke and make it run Saab would have had them on there 2 stroke rally cars back in the 50 and 60s
.

http://www.twostroke.co.uk/
here yah go

warrenp · October 5th, 2006, 02:09 PM

what this expansion chamber all about?
show me i'm a hands on type of guy

veritech-z · October 5th, 2006, 02:49 PM

That big tube on the right is the expansion chamber. I think they got around the oil pump by using an Aerocharger that has it's own supply of oil that you change every so often...It looks a lot like those rear mount turbo systems for cars.

warrenp · October 5th, 2006, 03:27 PM

oh ok simple enough i already have one i didn't realize what it was.
i have a stainless exhaust from a jet ski i parted out i thought i might use for this project.

rztmartini · October 5th, 2006, 06:39 PM

i think it really dpends on your motor. the banshee is a 2 cyl and while one cyl is on tyhe compression stroke the other cyl is on the intake stroke (kinda), alowwing all the air to go into one cyl, bypassing th eother. if it were on a 1 cyl like almost any other 2 stroke quad, engine the airflow would have to stop and start and stop and so on...a continual BOV might be able to be used to bleed off the boost when the reed valves are closed...interesting tho...

i always had a fleeting dream of turboing my 250 suzuki, but never really looked into it. the banshees alreay had a tight powerband, esp. with toomeys and mikuni carbs, i cant imagine what it would be like when it was boosted.

drzed · October 5th, 2006, 07:27 PM

It can be done!

Skidoo had a run of 670cc Turbo snowmobiles somewhere in the mid 90's. I've never ridden one but the new RX1 turbos (1000cc 4 stroke) sure move. I've looked into turbocharging a 2 stroke a little and it looks possible if you have the right type of two stroke engine. There are many different types - with and without reeds etc.. There is a chapter in the turbo book I have but it unfortunately doesn't get into specifics.

The idea is that you have to watch that you don't blow the mix right through the engine. I think that some of the Skidoos ran a rotory valve to try to eliminate this.

The detroits use the blower to give the air a push into the engine but the blower is a fixed ratio so it doesn't push too much air - or something like that anyway. I'm sure any of the mechanics on this site could explain it better.

I'm definately no expert but the idea is interesting eh? Good luck and keep us posted. I have a spare sled with a 600cc engine just begging for "more power".

warrenp · October 6th, 2006, 11:36 AM

well i just started friggan around.
the old ihi turbo i been holdin on to seems to be seized up. damn it!!!

luckly i think my buddy has one i can buy for like 25 bucks
i put the pb blaster to mine to see i could un seize it but i donno if it's gonn come out of it.

well if i hae to i also have some good t3's i could use but seemslike a smaller ihi rbh5 would better for the application.

also any one know where i can fine a flange for a ihi turbo? i ave the exhaust "out" flange but i need one to weld to the exhaust "IN" to the engine.

i could make one but i rather just order it.

bjhines · October 6th, 2006, 12:42 PM

Allison Diesel made a V-8 heavy equipment engine not too long after WWII... It was a direct injection 2 stroke with overhead valves... they have turbo and supercharged those types of engines for the last 65 years...

You guys are getting too hung up on the number of operational cycles...

The valvetrain is what makes or breaks forced induction suitability...

Any large engine will have some sort of positively actuated valve system... those are fine with forced induction applications...

THE PROBLEMS with small engines are the fact that they have NO VALVETRAIN... or they use simple reed/flapper valves that use ambient pressure to open and close them...

I have a gaggle of small model airplane 2 stroke engines... they work similarly to the chainsaw and weedeater engines in your garage...
The mixture is drawn into the crankcase... and then travels outside the cylinder liner to ports cut into the sides of the liner... the positioning of the ports is what determines the timing of the engine operating events.

These small engines CAN BE "SUPERCHARGED" with a tuned exhaust resonator that uses divergent and convergent cones at each end to set up a standing pressure wave... the pipe is tuned to a frequency that places the lowest pressure trough right at the exhaust port the moment it opens to expel gasses... they are very peaky by design... kind of like an organ pipe plays only one note.... the engine will produce AMAZING POWER at only one speed... the tuned pipe note's speed....

warrenp · October 6th, 2006, 02:11 PM

there isn't any supercharged diesels.
it's just not effictive. they can't make enough boost.
seen people try and they ar not "true" suprechargers they only force air not fuel and air.

true as in 6:71 4:71 4:53 etc.. top mount.

a blower on a 2 stroke diesel is NOT for proformance!

veritech-z · October 6th, 2006, 02:29 PM

Why is anything but a roots blower not a "true" supercharger? That's news to me...also, you should be able to make whatever boost you need by fiddling with your pulley sizes, no?

October 4th, 2006, 03:56 PM	#1
warrenp Member Join Date: Apr 2001 Location: boothbay Posts: 267	how to turbocharged 2 stroke ???? any one have info on turbocharging a 2 stroke like a snowmobile. i have a small 340 Polaris and a ihi RBH5 i would like to utilize. i think they would make a good match. also I'm trying to be cheep on this. so what could i use as a oil scavenge pump? i found pumps but they want almost $200 for one. seems like there must be some alternative __________________ no replacement for displacement

October 5th, 2006, 04:27 AM	#3
dr_hunt Super Moderator Join Date: Sep 2004 Location: Right Here, I think. Posts: 2,507	Considering the detroit 2 stroke diesel engines work well, I son't see anything that makes it so that it won't work. Detroits have a large round expansion chamber and open exhaust and are blown and turbo'd. Ditch the reed valve setup as it's no longer needed. Would be interesting to see how it worked. __________________ SEZ 1.36 60', 9.84 @ 132.62 through mufflers. Alb. National Dragway 9.90 @ 136.45 all motor. Don't waste your time on someone who isn't willing to waste their time on you.

October 5th, 2006, 07:29 AM	#4
veritech-z Mad Max Zed Join Date: Mar 2006 Location: tampa, FL Posts: 1,555	I'd actually heard that it can't be done, If you do find a way, be sure and let us know...It seems like all the makers of outdoor power equipment would rather turbo/supercharge 4 stroke enignes...seeing as how they have no problem doing that, I would HAVE to think that if it were feasable, SOMEBODY would have released an OEM turbo quad/jet-ski/snowmobile by now... __________________ -Max www.maxacree.com www.360ed.com "I put on my robe and wizard hat.."

October 5th, 2006, 08:26 AM	#5
warrenp Member Join Date: Apr 2001 Location: boothbay Posts: 267	whe ni did a serch i found a guy that turboed a vespa seems to work ok. but there wasn't any info on it. believe me i have made up my mind. i'm puttin a tubo on it! where's the expansion chamber located on a detroit???? detroit 2 stroks have to have a blower or i do not htink they wouldn't run or at least not properly. also along with my serches some one made a kit for a banshee at one time. i don't think it's made any more __________________ no replacement for displacement

October 5th, 2006, 08:34 AM	#6
veritech-z Mad Max Zed Join Date: Mar 2006 Location: tampa, FL Posts: 1,555	Vespas are 2-stroke? I thought they were 4 cycle. __________________ -Max www.maxacree.com www.360ed.com "I put on my robe and wizard hat.."

October 5th, 2006, 02:34 AM	#2
a6t8vw Member Join Date: Jun 2006 Location: The O.C. Posts: 278	ive seen only 1 turbo 2-stroke in my life, it was a 500cc banshee out at glamis CA. The owner didnt seem to get it to run that great... Sounded SUPER nasty and had a very narrow power band... secondly a 2-stroke needs the Expansion chamber to extract the gas's from the motor.. and a turbo would disrupt that theroy all together... im not saying it cant be done, but it woudlnt run that great.. for one thing the piston on the up stroke draws air in thrugh the REED VALVE which is a one way valve. When the piston is going down the valve is closed and the air/fuel under the piston and crankcase is pressurized forceing the air up the transferports and back on top of the piston.... so if the turbo was spooled produceing boost it would open the reed valve ALL THE TIME when the piston is creating pressure on the down stroke to close it so basicly the turbo would FIGHT with motor. and haha just thought of that ^^ your best bet to make power with a 2-stroke is porting and a high compression head... and a high octane fuel to back up the high compression andy

October 5th, 2006, 10:20 AM	#7
SHO-Z Member Join Date: Jan 2003 Location: Buckeye AZ Posts: 595	Two strokes require the gas/oil mixture going through the lower end for lubrication. The crank seals are not designed for a whole lot of pressure. If you really want to get some more HP out of the machine install an expansion chamber installed for the engine, match the ports between the lower end cases and the barrel. If it has a chrome lined barrel you cannot do much with the ports in the cylinder area. Another old trick is the stuff the crank. Some cranks have holes in them, we used to fill these holes with magnesium and get some added HP. If the engine has reed valves in the intake get some high performance ones that are a little more flexible. Hopping up a 2 stroke is a whole new world. To put a turbo you would have to have some type of electric oil pump to lube the turbo. If you could turbo a 2 stroke and make it run Saab would have had them on there 2 stroke rally cars back in the 50 and 60s .

October 5th, 2006, 12:25 PM	#8
Sam280Z Member Join Date: Feb 2002 Location: Baton Rouge, LA Posts: 120	There is a whole 4 page chapter on it in this book: http://www.amazon.com/Turbochargers-...e=UTF8&s=books

October 5th, 2006, 01:54 PM	#9
a6t8vw Member Join Date: Jun 2006 Location: The O.C. Posts: 278	heres a cool turbo quad useing 1300cc streetbike motor 4-stroke http://videos.streetfire.net/categor...DF995CEDC9.htm i actually found some turbo-2 stoke stuff this guy builds em http://www.trickracing1.com/home.html scroll down to turbo stuff

October 5th, 2006, 02:09 PM	#12
warrenp Member Join Date: Apr 2001 Location: boothbay Posts: 267	what this expansion chamber all about? show me i'm a hands on type of guy __________________ no replacement for displacement

October 5th, 2006, 02:49 PM	#13
veritech-z Mad Max Zed Join Date: Mar 2006 Location: tampa, FL Posts: 1,555	That big tube on the right is the expansion chamber. I think they got around the oil pump by using an Aerocharger that has it's own supply of oil that you change every so often...It looks a lot like those rear mount turbo systems for cars. __________________ -Max www.maxacree.com www.360ed.com "I put on my robe and wizard hat.."

October 5th, 2006, 03:27 PM	#14
warrenp Member Join Date: Apr 2001 Location: boothbay Posts: 267	oh ok simple enough i already have one i didn't realize what it was. i have a stainless exhaust from a jet ski i parted out i thought i might use for this project. __________________ no replacement for displacement

October 5th, 2006, 06:39 PM	#15
rztmartini Member Join Date: May 2005 Location: so cali woot woot Posts: 393	i think it really dpends on your motor. the banshee is a 2 cyl and while one cyl is on tyhe compression stroke the other cyl is on the intake stroke (kinda), alowwing all the air to go into one cyl, bypassing th eother. if it were on a 1 cyl like almost any other 2 stroke quad, engine the airflow would have to stop and start and stop and so on...a continual BOV might be able to be used to bleed off the boost when the reed valves are closed...interesting tho... i always had a fleeting dream of turboing my 250 suzuki, but never really looked into it. the banshees alreay had a tight powerband, esp. with toomeys and mikuni carbs, i cant imagine what it would be like when it was boosted.

October 5th, 2006, 07:27 PM	#16
drzed Member Join Date: Nov 2004 Location: Langley, BC Posts: 107	It can be done! Skidoo had a run of 670cc Turbo snowmobiles somewhere in the mid 90's. I've never ridden one but the new RX1 turbos (1000cc 4 stroke) sure move. I've looked into turbocharging a 2 stroke a little and it looks possible if you have the right type of two stroke engine. There are many different types - with and without reeds etc.. There is a chapter in the turbo book I have but it unfortunately doesn't get into specifics. The idea is that you have to watch that you don't blow the mix right through the engine. I think that some of the Skidoos ran a rotory valve to try to eliminate this. The detroits use the blower to give the air a push into the engine but the blower is a fixed ratio so it doesn't push too much air - or something like that anyway. I'm sure any of the mechanics on this site could explain it better. I'm definately no expert but the idea is interesting eh? Good luck and keep us posted. I have a spare sled with a 600cc engine just begging for "more power". __________________ '71 240Z 2.8l, E31, 3 x 45 webbers, cam, header, 5 spd, 4.38 R180, 13.44 @ 101 '74 260Z '82 turbo engine, SDS EM1, Rayjay turbo, 550cc, MSD 6A, NPR intercooler, 3" exhaust, 3N71B, 3.90 R200, MT slicks, 11.15 @ 120 Coming soon - larger turbo and more boost!!!

October 6th, 2006, 11:36 AM	#17
warrenp Member Join Date: Apr 2001 Location: boothbay Posts: 267	well i just started friggan around. the old ihi turbo i been holdin on to seems to be seized up. damn it!!! luckly i think my buddy has one i can buy for like 25 bucks i put the pb blaster to mine to see i could un seize it but i donno if it's gonn come out of it. well if i hae to i also have some good t3's i could use but seemslike a smaller ihi rbh5 would better for the application. also any one know where i can fine a flange for a ihi turbo? i ave the exhaust "out" flange but i need one to weld to the exhaust "IN" to the engine. i could make one but i rather just order it. __________________ no replacement for displacement

October 6th, 2006, 12:42 PM	#18
bjhines HybridZ Supporter Join Date: Dec 2004 Location: Cary NC Posts: 1,413	Allison Diesel made a V-8 heavy equipment engine not too long after WWII... It was a direct injection 2 stroke with overhead valves... they have turbo and supercharged those types of engines for the last 65 years... You guys are getting too hung up on the number of operational cycles... The valvetrain is what makes or breaks forced induction suitability... Any large engine will have some sort of positively actuated valve system... those are fine with forced induction applications... THE PROBLEMS with small engines are the fact that they have NO VALVETRAIN... or they use simple reed/flapper valves that use ambient pressure to open and close them... I have a gaggle of small model airplane 2 stroke engines... they work similarly to the chainsaw and weedeater engines in your garage... The mixture is drawn into the crankcase... and then travels outside the cylinder liner to ports cut into the sides of the liner... the positioning of the ports is what determines the timing of the engine operating events. These small engines CAN BE "SUPERCHARGED" with a tuned exhaust resonator that uses divergent and convergent cones at each end to set up a standing pressure wave... the pipe is tuned to a frequency that places the lowest pressure trough right at the exhaust port the moment it opens to expel gasses... they are very peaky by design... kind of like an organ pipe plays only one note.... the engine will produce AMAZING POWER at only one speed... the tuned pipe note's speed.... Last edited by bjhines; October 6th, 2006 at 12:44 PM.

October 6th, 2006, 02:11 PM	#19
warrenp Member Join Date: Apr 2001 Location: boothbay Posts: 267	there isn't any supercharged diesels. it's just not effictive. they can't make enough boost. seen people try and they ar not "true" suprechargers they only force air not fuel and air. true as in 6:71 4:71 4:53 etc.. top mount. a blower on a 2 stroke diesel is NOT for proformance! __________________ no replacement for displacement

October 6th, 2006, 02:29 PM	#20
veritech-z Mad Max Zed Join Date: Mar 2006 Location: tampa, FL Posts: 1,555	Why is anything but a roots blower not a "true" supercharger? That's news to me...also, you should be able to make whatever boost you need by fiddling with your pulley sizes, no? __________________ -Max www.maxacree.com www.360ed.com "I put on my robe and wizard hat.."

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