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Dodik 11-04-2011 07:08 AM

look here to turbo your car

or here to supercharge it

wolflegacy 11-04-2011 10:15 AM


Originally Posted by Flyboy888 (Post 3620980)
I was thinking the m62 as well or the one from the older grand prix GTP. I believe its the m90? Not sure tho.

the m90 will not fit under your hood without modifications its too big


Originally Posted by BAC5.2 (Post 3621112)
Don't let your boos spike!

i am sorry i meant "boost" if that is what bothers you


Originally Posted by BrandonJ 2001 GT Limited (Post 3621117)
Another thing I just thought about. Both the Cooper S and Cobalt SS started with superchargers and went to a turbo in the later years and current models. IMO, if the SC is/was a great idea on a 4cyl....why didn't those two cars stay SC?

because when you supercharge an engine it is also uses power form the engines crank therefore actually taking away some of your hp
and the size of the supercharger itself is limited to the size of your engine
but a turbo because it uses only your exhaust gases it doesn't take away any of the produced hp and you can put it as big as you want providing you have strong internals and will not mind the lag from the bigger turbo)

the reason i see that supercharging is better for our cars is because at the low boost that the cars will run sc is actually more powerful
all the power comes to you immediately of the line not like the turbo where you have to keep it over 3000rpm to get the benefits
sc have no lag

BAC5.2 11-04-2011 10:27 AM

What bothered me was that you were wrong.

You are also wrong to think SC's have no lag, and that "all that power comes immediately off the line". It doesn't. SC's have boost proportional to engine RPM up to a bypass pressure. You don't have positive manifold pressure at idle.

9 times out of 10, turbocharging is the more efficient way to make power. This falls apart at the extreme high end, but holds mostly true for your average car.

If you want to do it cheaply, do what BrandonJ said. Buy some used parts from a WRX (headers, uppipe, turbo, downpipe), then have other various pipes put together to get it to work. Notch the crossmember, and have at it. You can drill or cut the tips off of your injectors, or run newer injectors from whatever model matches your car (either top or side feed) to get the flow you need without needing a 5th injector (which is ghetto). Tune it with a PP6 or build a Mega Squirt (I'd do the latter).

Run ~6psi max on a TD04 and you'll probably make in the 180 whp range without MUCH risk.

Keep in mind, the car won't be FAST by any stretch. It'll still be slow, but it'll probably keep you entertained.

Dodik 11-04-2011 10:57 AM

totally agree with what bac said boosting a stock n/a motor will only do two things. give you those mad props from all of your friends and placebo effect will make you think its fast and shit.

sunny_d 11-05-2011 09:54 AM

The reason sc are more popular with V8's from what I've seen, is, they are easier due to the exhaust. Also since the boost is proportional to RPM's they can run bigger pulleys due to more existing torque, and have "more" boost at lower rpms. Both can cause detonation if you run lean. Turbo's are better on smaller engines, because they naturally don't have much power on the low end, and usually run higher rpms for peak power, which works great with turbo spooling and lag time. I've driven a sc Pontiac gtp that was all done up, and he even had a little lag. Nothing like my fp 3065 on my talon though! Haha

Would write more but in a deer stand and my hands cold

Flyboy888 11-05-2011 11:38 AM

Ahhh ok, tis a good point

Osei 11-05-2011 05:19 PM


Originally Posted by sunny_d (Post 3622217)
Would write more but in a deer stand and my hands cold

May you have good fortune!


BrandonJ 2001 GT Limited 11-06-2011 05:17 PM


Originally Posted by BAC5.2 (Post 3621370)
You can drill or cut the tips off of your injectors, or run newer injectors from whatever model matches your car (either top or side feed) to get the flow you need without needing a 5th injector (which is ghetto).

AVO puts a 5th injector on their kits...

So I guess the maker of the kit we're trying to model is ghetto and hacking your injectors isn't?

BAC5.2 11-06-2011 06:29 PM

Correct. A 5th injector before the throttle body is ghetto. Modding stock injectors isn't.

BrandonJ 2001 GT Limited 11-06-2011 07:15 PM


I'd trust AVO who has put the kit on a dyno and spent $$$$ in R&D vs drilled out unmatched injectors from someone's drill press :lol:

BrandonJ 2001 GT Limited 11-06-2011 08:25 PM

Also, if the 5th injector is so ghetto...then why did Subaru themselves put on on the 1994 WRX RA?

BAC5.2 11-07-2011 04:32 AM

I'm not suggesting a simple drill-out and toss-in, that would be stupid.

When you buy DW Injectors, or PE injectors, or Perrin injectors, you are getting nothing other than modified stock injectors with varying levels of flow and pattern matching (DW, for example, sends you injectors flow matched to, typically, 1%. Perrin used to send out modified, but unmatched and untested injectors).

The 5th injector in the RA wasn't used on the road car, and it wasn't before the throttle body. It was present, but never used. That same car used a step-colder spark plug in the #4 cylinder.

I'd use a set of matched and verified modified stock injectors, or a set of take-off higher flow injectors from a different model (whichever ones fit) instead of a 5th injector pre-throttle body. Modified injectors have been dyno-tested plenty. Lots of 500+whp guys on Nasioc run modified injectors. I did on my first-gen Turbo, to the tune of just under 400whp and just over 400ft-lbs.

Flyboy888 11-07-2011 04:54 AM


Originally Posted by Dodik (Post 3621119)

After seeing this I'm now back to turbo interest lol. Anybody know bout the various kits their are? The avo kit seems to be best bang for your buck, but $3800 is a lot of buck.

BAC5.2 11-07-2011 04:59 AM

Just do it yourself with OE WRX parts. Cut a notch in the crossmember, use a WRX manifold, uppipe, turbo, downpipe, intercooler (top mount if you trade hoods with a Baja Turbo, or front mount if not), then tune it with a Mega Squirt or PP6. You can EASILY come in under $2k if you do the work yourself.

Flyboy888 11-07-2011 05:09 AM

Right, like the other guy did. What about cuting the hood and getting a wrx scoop? I figure the scoop would cover the cuts. Figure its cheaper than a $300-400 Baja hood (which I would prefer). And then, what all taps would I need to do? Like for oil and whatnot.

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