First of all this is more of a dilema, I already know the answer to the first question: What will work better for me 3" piping or 2.5" ?

I know that 2.5 will work the best, because it will lose less fluid velocity and takes way less volue to fill...

I am curious to know how much power will I lose if I stay with the 3" because I already have a few bends and couplers. Just wanted to know what should I expect to lose by staying with the 3" vs 2.5" ? I would be great if you guys told me about your personal expirience with situations like this...

Status- Need to do break-in...



Try not to challenge me, I'd rather tie up than lose. Either way you NEVER WIN.... - Me..

It is not so much about losing power, but losing response. The larger the volume the turbo must pressurize, the longer it will take to reach your desired pressure. Large intercoolers, long piping, and large diameter piping increase your total volume. Regarding velocity, your throttle body diameter stays the same no matter what intercooler piping you choose. You could feed that TB with 1" or 3" diameter piping and the velocity will be the same as always after it expands into the throttle body and beyond. Now, there is something to be said about reducing pumping losses by choosing your piping diameter. Every time you change the diameter of the pipe or turn, you lose some energy. 3" piping dumping into a stock throttle body will lose energy as you make that abrupt change in diameter. 1" piping dumping into a stock throttle body will lose energy as well. You want to make as gentle of a transition as possible. I suggest you start your intercooler piping at whatever diameter the compressor outlet is. Use a long exducer (ideally less than 10 degree angle) to transition to whatever diameter matches the intercooler inlet (this might require two separate exducers). Then start another pipe with whatever diameter matches the intercooler outlet. Use a long exducer (ideally less than 10 degree angle) to transition to whatever diameter matches your throttle body (this might require two separate exducers). I have assumed that your throttle body is appropriate diameter for your power goals. That may not yield the absolute peak power producing setup, but it is certainly a good start.

Corbin
'95 ESI-T

Now with more power and fewer leaks



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