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Old 09-16-2004, 02:37 AM   #1
reddevil
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Default Can "new" pistons cause low power?

Ok, for those who didn't know it, I damaged the top of #4 piston and destroyed the ring lands of said piston. I did damage/scratch the cylinder wall, but nothing close to disasterous. I did this by running too much boost and too much nitrous combined with no aftermarket fuel enhancement and no timing management. This was done on a NA 1990 2.2 that had just had new rings and rebuilt heads on it. I was then branded with the word "idiot" on my forehead. I was greedy and impatient.


I replaced the pistons with a brand called "Rock" and the rings with a quality japanese brand (cant remember the name). Absolutely no problems when I finally restarted the motor. Runs and idles like a dream, maybe a weird dream, but a dream none the less.

But....... I have about 225 miles on this engine so far. I am not hammering on the engine at all and have yet to hit 5000+ rpm. But when I do floor it, there is a nice smooth power but it feels like **** compared to my old engine. There is NO punch now. Car can easily go fast, but not accelerate fast. When running up to 80 in 5th, the car doesnt complain in the least, no stuttering just no oomph.

My question is, could I have gotten pistons that are lower compression that OEM stock pistons? So lets say my compression ratio drops from NA compression (which is what 9.5-1 9-1?) to lower, somewhat nearer to turbo 2.2 compression ratio. Would this rob power but still run well?

Thanks.
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Old 09-16-2004, 06:05 AM   #2
wrx plus
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Yep, lower compression = lower power. However lower compression also = ability to run more boost. But the pistons you got are from a manufacturer I have never heard of, if you are planning to go back on boost and NOS make sure the pistons are designed for it.
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Old 09-16-2004, 12:20 PM   #3
DLC
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Time for boost...
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Old 09-16-2004, 01:06 PM   #4
Kevin Thomas
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Quote:
Originally Posted by reddevil
My question is, could I have gotten pistons that are lower compression that OEM stock pistons? So lets say my compression ratio drops from NA compression (which is what 9.5-1 9-1?) to lower, somewhat nearer to turbo 2.2 compression ratio. Would this rob power but still run well?

Thanks.
Yes, you could have gotten pistons that are lower in compression then that of OEM stock pistons. If your compression ratio dropped somewhat to turbo 2.2 compression ratio, it would rob you of power but still run well.

Like posted above, it would allow you more boost to run safely as well provided the pistons are designed similar to the stock pistons (I'm talking down to the metal as well, not some different cast if that's possible).
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Old 09-16-2004, 06:07 PM   #5
powerlabs
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You were running boost and nitrous, you took them off, and now the car feels slow... Where is the surprize?
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Old 09-17-2004, 12:11 AM   #6
reddevil
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I know what are are saying, and I suspect that might be a little bit of the problem, but I did take it to the track a few times before the nitrous and boost, and the way it reacts now is nothing like it felt when I rebuilt it 3000 miles ago. hmmm, 3000 miles, I though that was when I was supposed to change the oil, not the pistons.
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