i want a street car that can haul ass. Both 1/4 and track use. ThanksRS25.com said:What's your goal for the engine/car? 1/4 mile times? Drivable in city with torque... there are a few factors to consider before just getting boost.
And yes, you'll need a much beefier transmission. The standard Subaru trannys fall apart with only a few pounds of boost over 10psi.
Like he said, nevermind the strength of the factory pistons: you'll definately need a lower compression ratio than the stock (almost) 10:1! Approximately 8.5:1 is suppossed to be the ideal CR ratio for a super charged application (yes, a turbo is a form of supercharger).5252 said:1. now we're talking!
2. i wish! i have rods, 8.5 to 1 pistons etc but that's where i start calling it "big" boost. some day.
3. transmission. a big trans mod will be necessary
Well, actually, I am at 14 psi at initial onset and settles to 12 psi. This is also NOT how I drive my car however. I have yet to floor my car. I am too paranoid on breaking again. On the dyno, I didn't push it. Shiv did. Plus it is a controlled situation. On the street I am running up to 12 psi (looking at the gauge alot) Not WOT. It will go to 14 psi if I floor it. When I have a heat soaked TMIC, I ping a bit so I am careful to to push it too hard. I need to fine tune the TEC a little more. I have yet to have the EBC hooked up to the TEC. At the moment, I am using a MBC that Shiv hooked me up with. As for injector duty cycle... 72% at 14 PSI and I could easly go up higher in boost. With my built up block and such I really need to beef up my top end now. The engine needs to breath better to take advantage of those high booost levels. So, if you are thinking of going to 15 PSI and up, I'd get a good head builder to make the heads breath better. As for my tranny?... I am xing my fingers. Shiv stopped at 14 PSI because of my tranny. I will leave it at that.There are a few. Hayscoob runs 15 I think, and kastle has run up to 20 psi I think. You should contact them or wait for a reply.
Graham said:I see your worry, now.
With aftermarket engine buildups, and especially Subaru's, its one thing after the next. You probably thought after the engine build you would be done with the car (well maybe the tranny). But, little do we know that the road to fast Subaru's, sorry to say, never ends.
Thats a great thought on having the car be able to run well at a wide variety of boost levels.