so who is gonna run this on their ski?
- Thread starter demolition_x
- Start date
turnagainhardcore
X-H2O
- Location
- Alberta
I think just to say you have it would almost make it worth it!!!!!
wydopen
onthepipe
- Location
- Goleta the Goodland
any one have pics??
dbrutherford
Parts Whore
- Location
- Fairmont, WV
There was pics years back on PWCT.
Shoot me an instant message on AIM, YIM, MSN sometime and I will share what I have. I am too lazy to upload pics anymore...
DAG
Yes, my balls tickled from that landing
- Location
- Charlotte, NC
9yr and a month bump lol.
That sounded nothing like I though it would. Sweet find
That sounded nothing like I though it would. Sweet find
Yeah sorry for bringing back memories but I'm really thinking about giving it the old college try. Turbos hold to much heat for a ski although they seem more ideal. I have been reading anything I can find on the internet about forced induction 2 strokes. Seems like the masters of the art are focused on snow sleds.
tntsuperjet
Tntperformance-engineering.com
- Location
- Georgetown ca
So here the deal with SC vs Turbo on a two stroke.
Having done a few turbo two strokes that make a very impressive HP LEVEL.
370 track hp out of a 1200cc twin.
Modern electronics have made forced induction two strokes viable for power and not drink gas like a carb version.
But here the issue. 4 stroke has 98% trap volume ratio for the compressed fuel.
Two stroke has less then 20%.
Power stroke is only 60-80 deg crank rotation on two stroke and it's 180 deg on a 4 stroke.
So the two stroke has a hard time over coming the power draw the SC requires to turn.
The turbo does two things.
Loads exhaust outlet which increases trapped pressure and it requires no power to rotate.
In order for the SC to add any significant power it takes a very unorthodox port configuration.
Also remember that all the guys in the long lost past who attempted SC on two stroke did so on non powervalve engines.
So they didn't get the added trapping pressure of the power valve.
But here your problem.
D.C. Always turns at a fixed rpm to engine speed.
Meaning at light throttle when your trying to do just a setup wake, your SC is just mowing through the fuel and a turbo isn't gonna spool
Having done a few turbo two strokes that make a very impressive HP LEVEL.
370 track hp out of a 1200cc twin.
Modern electronics have made forced induction two strokes viable for power and not drink gas like a carb version.
But here the issue. 4 stroke has 98% trap volume ratio for the compressed fuel.
Two stroke has less then 20%.
Power stroke is only 60-80 deg crank rotation on two stroke and it's 180 deg on a 4 stroke.
So the two stroke has a hard time over coming the power draw the SC requires to turn.
The turbo does two things.
Loads exhaust outlet which increases trapped pressure and it requires no power to rotate.
In order for the SC to add any significant power it takes a very unorthodox port configuration.
Also remember that all the guys in the long lost past who attempted SC on two stroke did so on non powervalve engines.
So they didn't get the added trapping pressure of the power valve.
But here your problem.
D.C. Always turns at a fixed rpm to engine speed.
Meaning at light throttle when your trying to do just a setup wake, your SC is just mowing through the fuel and a turbo isn't gonna spool
Quinc
Buy a Superjet
- Location
- California
Current attempt at building a turbo for an XL800:
http://www.greenhulk.net/forums/showthread.php?t=245557
http://www.greenhulk.net/forums/showthread.php?t=245557
@Quinc,
Nice looking build! I'm at work and only made it to page two but will read it all later.
@tntsuperjet,
Thank you for your input as well. I was considering building a pressure activated exhaust butterfly valve with a pneumatic linear actuator to help control exhaust flow. It would take some time to dial in, starting with no restriction and slowly working toward holes in my pistons. About the supercharger producing boost even at light throttle, how do car manufacturers get around this? A bypass valve? For instance on my lightning there was no boost when at light throttle but would wine and produce it instantly if you stepped on the gas.
Thanks,
J. Randall
Nice looking build! I'm at work and only made it to page two but will read it all later.
@tntsuperjet,
Thank you for your input as well. I was considering building a pressure activated exhaust butterfly valve with a pneumatic linear actuator to help control exhaust flow. It would take some time to dial in, starting with no restriction and slowly working toward holes in my pistons. About the supercharger producing boost even at light throttle, how do car manufacturers get around this? A bypass valve? For instance on my lightning there was no boost when at light throttle but would wine and produce it instantly if you stepped on the gas.
Thanks,
J. Randall
tntsuperjet
Tntperformance-engineering.com
- Location
- Georgetown ca
There was boost in your car but recirculating bov is common in daily sc production engines.
But % of over drive will help the sc produce smaller volume at low rpm and higher Cfm as rpm rises as the sc turns considerably faster then engine rpm so it's not a equal CfSM gain per rpm.
You have to map the SC volume and rpm to engine displacement so it runs in a linear increase in CFM as to increase boost as rpm rises.
Problem. Your ford at 4,000 rpm built boost regardless of throttle position. But you have the advantage of gears so you can cruise at low rpm.
Jetski is at 4500rpm just to stay on plane.
So there for your cruising at boosted rpm levels.
But % of over drive will help the sc produce smaller volume at low rpm and higher Cfm as rpm rises as the sc turns considerably faster then engine rpm so it's not a equal CfSM gain per rpm.
You have to map the SC volume and rpm to engine displacement so it runs in a linear increase in CFM as to increase boost as rpm rises.
Problem. Your ford at 4,000 rpm built boost regardless of throttle position. But you have the advantage of gears so you can cruise at low rpm.
Jetski is at 4500rpm just to stay on plane.
So there for your cruising at boosted rpm levels.
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tntsuperjet
Tntperformance-engineering.com
- Location
- Georgetown ca
If you run an EFI system with maf sensor you can build a rcv system that is throttle position activated and reduce the amount of air shoved through the engine but you will build more intake temps as the air will travel through the SC multiple times under light throttle cruising
At least I would have an unlimited supply of cold water for the air to water intercooler. Ecotrons makes a efi kit that has some excellent reviews obviously it would be more cost effective to just buy a big boy motor and run N/A. Just interested in the subject I guess.
http://www.ecotrons.com/products/400cc_to_800cc_engine_fuel_injection_kit/
http://www.ecotrons.com/products/400cc_to_800cc_engine_fuel_injection_kit/