I have a 94xp with a blown motor. I have a good stock garrett gt25 from my Nissan SR20. My question is has anybody ever tried to turbo a 657 with twin carbs? How did it turn out? Since the engine is blown I was considering switching everything to the fuel injected 800 since I have more experience with efi and turbo than carb and turbo, and honestly I don't even know if turbo on a carb is possible, but I do know how to get over 400hp out of a 2.0SR20DET (efi)... any comments are welcome but dont try to tell me not to do it, cause I'm doing something to it I just don't know exactly what yet.
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94xp 657 turbo?
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Dr Honda
Well-Known Member
Force feeding a regular 2-stroke doesn't work. Without an exhaust valve... you cant compress the air/fuel in the combustion chamber. also, since the normal 2-stroke compresses the air/fuel in the crankcase to force it up the by-pass ports... you may just split the big end of the rod.
There is a reason you never see it done.
Final thought... a GT25 would never work on a 650cc engine, unless it was spinning 15,000 RPM.
There is a reason you never see it done.
Final thought... a GT25 would never work on a 650cc engine, unless it was spinning 15,000 RPM.
purple_people_eater
New Member
plus i've never seen it done on a carb'ed motor. i've sc'ed a couple carb'ed corvette's but we had to use carbs designed for sc's so we that the inturnals would not get sucked out. and like dr honda said with not exhaust valve you can't build up compression, so you need to figure out how to make the compressed charge outside of the motor and the inject it. as far as a 787 rfi: Stay Away. they run good when they are running but get very expessive quick when they start having issues.
Well I never even thought about that I was blinded by weather or not you could run turbo on a carb or not. Well thanks for intelligent responses for a rediculous question. as for using the 787 rfi well there isn't much point in that now either. I have to do something to get more power I need some ideas. What about swaping the 657 for the carbed 787? Probably be better off just rebuilding the 657and buying a 96XP.
I know nos would work but its out of the question
I know nos would work but its out of the question
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Dr Honda
Well-Known Member
You can turbo with a carb. You can do both a "Draw Threw" or a "Blow Threw" system... but a blow threw is more work.
And... most of the people on this BBS will recommend that if you want a significant HP jump... just buy a bigger ski. I'm all for mods... but most mods on a JetSki will be expensive, with only a small gain.
And... most of the people on this BBS will recommend that if you want a significant HP jump... just buy a bigger ski. I'm all for mods... but most mods on a JetSki will be expensive, with only a small gain.
Ok if going that rout is not worth the rewards what about switching impellers? What would a good one for top speed and what would be a good one for acceleration? I have had to take the impeller out of mine only once since new and its still the original in there. If you're wondering its been a terrific ski for me till now and only had to do maintenance on it, not bad
purple_people_eater
New Member
impeller would be your best bet for getting more power. as far as the 95-96 xp 800's they have a diffrent bottom hull design. i love them and am completly happy with my ski set atm. solus concords are good for acceleration, idk about top speed tho.
oktain
Member
Brain storm idea... Why not adapt a Boondocker turbo kit for a snowmobile for your purposes? You can run the kit on carbed sleds and if you don't want to drop the coin for a brand new one you could always pick up a used kit. Lots of turbo mountain 2 strokes running around in BC, meaning that used kits should be available where you are.
I'm more of a sled-head than I am a ski-freak lol, but a 2-stroke ski engine is similar to a snowmobile engine, just designed for a different application and different power demands correct?
I'm more of a sled-head than I am a ski-freak lol, but a 2-stroke ski engine is similar to a snowmobile engine, just designed for a different application and different power demands correct?
good call oktain that is what got me thinking about running a turbo on my ski in the first place, I just don't know how to adapt the technologies together. thought... sleds run clutches and belts where there is none of that on a ski just a shaft to the impeller. now as far as building a set of engine mounts to make it line up, I don't hink that would be a problem but trying to mate the two probably would be a problem. and then there's cooling and electronics to worry about. Also wondering the posibility of adapting that turbo system to the seadoo engine, but as it looks now it doesnt sound like the seadoo engine could handle a turbo on it...
any more ideas? keep them comming. Expand on current ideas.
any more ideas? keep them comming. Expand on current ideas.
just like a car. i can't remember abut oil and coolant. would have needed a pump or something. I also used to have a s13 w/ s13black top. 246/268 on 11.5psi stock manifold... never dyno'd 15 with tubular and turbo back exhaust. car pulled like hell after turning up boost oh yeah, stock t25 as well. awesome car.
That's what I am running right now except mine is a red top. Rebuilding the engine right now for 400hp. Its not the same as boosting a car though 2 stroke seems to have issues with turbo set ups which is what I am trying to overcome. There is a turbo set up for the ski doo though Wich I am looking into options for. Just a note my s13 will pull 13.7 in the 1/4 on its current tune at 12.5psi with stock turbo and intercooler.
we mostly run 1/8 here in alabama. went 8.5xx in the 1/8 a few times. first pass in the 1/8 was 9.1xx. put some bf goodrich on it and got it to dead hook. had a 5 lug swap and 1995 se wheels stock s14 tire size bf goodrich g force sports...
back to the ski. i forsee alot of fab work to even attempt the turbo set up plus think of how hot it's goig to getunder your seat. need to vent that some how. the 4 banger ski's that are boosted probably have preparations as far as ventilation.
back to the ski. i forsee alot of fab work to even attempt the turbo set up plus think of how hot it's goig to getunder your seat. need to vent that some how. the 4 banger ski's that are boosted probably have preparations as far as ventilation.
I don't think cooling will realy be too much of a problem as it is fresh water cooled and if I can find out more about doing this ski doo engine swap then I might do that and I will have to figure out something with the cooling at that point since the ski doo is closed cooling, maybe a liquid to liquid heat exachanger off a 5.7 mercruiser or something like that, which is set up to cool 300hp, a little extra cooling never hurt anybody. I kinda like doing this kind of stuff, lol which is probably why I have way too many projects on the go right now, SR build (nearly complete), sea doo build (nearly started) and a pathfinder to tinker with (seems to be on going) plus a 47ish plymouth 2 door I will be building as a resto-mod after these are all finished, what an expensive hobby I've found myself.. at least its worth it in the end.
By the way, what happened to your s13? you said you "had" one? coupe or hatch? man I love getting beside mustangs and Camaros with that thing, they say he who laughs last laughs best ... Fox you know what I mean =)
By the way, what happened to your s13? you said you "had" one? coupe or hatch? man I love getting beside mustangs and Camaros with that thing, they say he who laughs last laughs best ... Fox you know what I mean =)
i sold it, just got out of it completely. it was a striper 89 hatch, except it had the lip and mudflaps from factory. 300 j-yard car no title, and applied and got one..hks ssqv and buddy club spec 2 were a few tasteful mods along with kouki tails. s14b seats, perffect dash, b&nm shifter, godspeed fmic, spec stage 3.. it goes on and on...i had a mustang at the same time. 1992 foxbody coupe slammed on 17" staggered prostars. build rearend, 5 lug swap he whole nine yards. i could whoop up with a domestic or import!
crisso
New Member
A good reliable turbo on a 2 stroke is hard to run.No oil pressure to keep the turbo from hooking up.Carbs on force fed have to be all o-ringed and that costs big.There is stuff you can buy but it will cost.
Just my opinion but skis should be easy and fun and if you want to go fast,have 2 skis.
I got 2 Ducati's.An ST for the nice rides and an older MHR when you want to wring it's neck.Just my op.
I love your idea though.It would really crank
Just my opinion but skis should be easy and fun and if you want to go fast,have 2 skis.
I got 2 Ducati's.An ST for the nice rides and an older MHR when you want to wring it's neck.Just my op.
I love your idea though.It would really crank
huh ? you can easily force feed a 2stroke
we do 200-275 on GT28s on 600-800cc ski at 9k, gt25 only running 6k or whatever you can run the numbers but it probably would work even on a 800cc sea, more then likely with the .86 turbine
blow thru, pleumn, boost refrence your carbs, raising rate fuel pressure reg, fuel pump to match if you cannot keep up the psi.
oil pump and res,
egt and af and go
we do 200-275 on GT28s on 600-800cc ski at 9k, gt25 only running 6k or whatever you can run the numbers but it probably would work even on a 800cc sea, more then likely with the .86 turbine
blow thru, pleumn, boost refrence your carbs, raising rate fuel pressure reg, fuel pump to match if you cannot keep up the psi.
oil pump and res,
egt and af and go
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