Limitations of 2.5" Intercooler Piping?
 

I know I've read this before, but I can't seem to find it through searching.

What are the restrictions of running 2.5" intercooler piping?

2.5" should be good up to XXX whp.

Oh, and in case you're wondering, I'm thinking of upgrading to the R85 if that changes anything.

Thanks.

good enough for approx. 500 - 600 rwhp ....I think the CFM is about 750ish +/-100?

I calculated some numbers based on Corky Bell's recommendations in this thread:
https://www.rx7club.com/single-turbo-rx-7s-23/wnen-does-3-ic-pipe-max-out-298757/

-Max

The compressor outlet on the R85 is 3", but has a thick wall. I measured the ID at 2.375", which I am sure is still bigger than compressors that have a 2.5" OD outlet. I had a 2.75" OD 90 degree bend welded onto the compressor housing on my car.

The numbers I calculated in that other thread used 2.5" (for example) as the ID, which of course is not quite right. But then again, the HP numbers were also for piston engines, and that isn't right either. :) And the mystery of why turbo compressors have relatively small outlets for the HP potential remains a mystery.

-Max