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I have a OBS with the 2.2L motor.

I was talking Bret Carter at Flatirons subaru the other day and he said that the 2.2 motor will take more boost then the 2.5 motor what is everyones feeling on this.

and what horse power are people getting out of the 2.2 motor?




:devil:
 

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That's a ridiculous statement. Sure, the 2.2L engine will handle more boost (stock) than the 2.5L engine will (stock) because it has a lower compression ratio. But boost does not mean power.

Theoretically (made up numbers here, kiddies) a 2.2L engine with 10psi boost wouldn't touch a 2.5L engine with 5psi. But if you put lower compression pistons in the 2.5L engine, then you could run more boost into the 2.5L block. That's obvious.

But the real question should be something like:

I can get more power with a properly built 2.5L turbo engine than a 2.2L turbo engine. Is this true? All things equal, the 2.5L engine with more displacement could probably do a better job, but then again there are 1.0L engines out there that make 1,000+ hp, so it all depends on how much you want to spend...
 

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Okay the fastest recorded 1/4 mile impreza is Tony Rigolli in Australia who is running 2.2 that has been bored and stroked to 2.4 liters. However the car is purpose built.

The highest horsepower Impreza (or Subaru for that matter) that I have ever heard of is any one of the Jun tuned Imprezas in Japan that are pumping out over 600 hp at the crank. All of these use a 2.5 block.

Regardless of these facts, your engine will handle a little (not a lot) more boost than a 2.5 liter. And whether you turbo or supercharge the engine you will have a little more room to play with as far as ignition timing goes.

Now whichever forced induction method you should use depends largely on you. If you are looking for a slightly flatter overall torque band and don't mind a little lag down in the powerband, then perhaps you should try a turbo kit.

If you would like a car that is always turning some boost, has a little higher peak horsepower, but has a fairly inclined powerband, then a centrifugal supercharger kit, like the one I am almost finished with, might be the way you want to go.

Either way the car is going to be faster than most domestic v8s, 2.2 or not. As long as you have proper engine management.

If you have any questions about any of this, feel free to email me. I do have some working knowledge on the subject at this point.
 
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