ThE sPaCeCoWbOy

actually when i used the 30% i was using in a non-ideal scenario.....

from what ive been reading to gain 100% power, 17 psi is used....roughly....so 12 psi can be about a 60% increase 7.5 psi 40 % increase....so i took a shot on the 30% for 5 psi....since supercharger isnt 100% efficient and non-ideal world....dont ask what website i got this from....i forgot....its been awhile back

anyways if the 951 puts out 240 HP with 12 psi, then it really doesnt match the numbers....
135*.6=81hp
135+81=216hp

but if i took the 944 HP
150*.6=90HP
150+90=240HP i get the numbers

im probably doing something wrong so correct me....

if the turbo was 80% efficient, then the number come close....but is he difference between turbos %E and a SC by 20%?

thanks,
space

Greg Hammond

I think you're forgetting that the 951 doesn't produce -anywhere- near 240 RWHP at stock boost levels. My stock-boost 951 with a larger than stock K-27#8 hybrid turbo with roughly 80% efficiency produced 197 RWHP at normal temperatures. So, I got 135+62 HP at 11 PSI.

As for efficiencies of turbochargers vs. superchargers -- you hit the nail on the head with that one. Turbos are MUCH more efficient and have NO parsitic loss when compared to a SC. Keep in mind the "only" real benefit to a SC over a turbocharger is the boost at low engine RPM. Disadvantages are parasitic losses, inreased heat management issues, and mechanical reliability concerns.

If you're replacing your pistons with turbo-spec pistons, and lowering your compression ratio in the process - you could consider having a custom exhaust manifold and intake plenum designed, and make use of a home-brewed turbo arrangement.

Greg

ThE sPaCeCoWbOy

for my exhaust manifold, i have MSDS headers...im going to open the exhaust up to 3 inch to get as much flow out as possible...

intake, i was thinking of some designs that i think would make some improvement but until i get a different stye supercharger, i'll have to keep my setup....since the SC i have has its own intake manifold....

also i think you have your numbers mixed up....

you posted 197 RWHP but when you added the HP together you added flywheel HP....im guessing about 17-20 % drivetrain lose so if i took your 197 RWHP, i get 236.4 HP flywheel...close to the 240....double check my calc....

thanks,
space

Luke

ThE sPaCeCoWbOy,

Sounds like you've invested quite a bit of money. I hope you get the outcome you deserve.

ThE sPaCeCoWbOy

im guess when its all done, i should have 10K with everything including the car....and if all goes right, i'll have more HP then the 951....
i just called a company about the supercharger and they can beef it up for me so i can run even more boost.... <img src="graemlins/bigok.gif" border="0" alt="[thumbsup]" />

thanks,
space

Luke

would you be interested in a DEFUNCT'ed 951 tranny? It needs a 2nd gear. $350! it's worth $575 as a core charge. <img src="confused.gif" border="0">

ThE sPaCeCoWbOy

sorry....done got another tranny also ....its from a 944S2....if i get another tranny, i would probably go with the 6 speed....

thanks for the offer though...

space

ThE sPaCeCoWbOy

sorry...got over excited again.... <img src="graemlins/jumper.gif" border="0" alt="[jumper]" />

Luke

no problemo

Danno

[quote]and if all goes right, i'll have more HP then the 951....i just called a company about the supercharger and they can beef it up for me so i can run even more boost....<hr></blockquote>I doubt you'd get more power than a 951 for the same boost. Stock 951 gets about 185rwhp @ 11psi boost (951S is about 210-220rwhp). Assuming you have the same efficiency from the intercooler and same intake-air temps, you'll still have the parasitic loss of driving the supercharger.

Luke

well it's given that a turbo is more efficient tha a supercharger Danno so I interperited it as him saying that he will eventually run more boost than a stock 951. <img src="confused.gif" border="0">

ThE sPaCeCoWbOy

if i run 12 psi, i'll have the nitrous to back me up.....but another thing im looking at too is my gearing is also lower then a turbo....so for stop light to stop light, i think i have the advantage....

but i did find a company that will beef up the supercharger so i guess the 12 psi is going to be too low for me now....i think i'll put the 12 on there, see what it does for awhile, break in boost, then move up....

i dont know......i got a good idea on the power i want now and im going to expect...

anyother questions someone wants to ask about this rebuild?...be more then happy to answer...

thanks,
space

Luke

you're going to eat up tires like a **** (pardon my french ) with the shorter s2 gearing and the lack of boost threshold, you'll burn off tires quicker than heck. Do you have a rubber center clutch. I would deffinately get a cup or Center force before you get that kind of power to the ground.

ThE sPaCeCoWbOy

<img src="graemlins/roflmao.gif" border="0" alt="[hiha]" /> ....****....gotta love that....

i figure tires might be a problem...im going to get some wider wheels later on down the road....might help with the keeping the spinning tires down.....of course i might have to start off in 2nd on this car.....

i got a clutch from vertex which replaces the rubber clutch and has springs and whatnot...im hoping this does me good....

anymore?

thanks,
Travis

Luke

you shouldn't have a problem starting in 2nd on the s2 box. My buddy has a great s2 and he always (pretty much) starts in 2nd. It's a short 1st. You're just gonna burn it off!