Well, didn't really get a solid answer on the question so I might as well start another thread. Didn't find any thing through searches so...

What are advantages/disadvantages of going with 2.5" over 3.0" charge pipes?

I believe one person said spool time would be a tad slower due to the extra volume in the pipes. Anyone verify? I would think, even when you get going, the 3" pipe would a good deal more cfms and if your throttle body, intake manifold, and head can flow it.

Any input guys?

 

I would go with 2.5 unless you are running a HUGE turbo... thats my opinion though, somebody else might say differently.

 

i was about to say that this topic has been beat to death but the search doesn't work so i guess it's cool. all i have to say is that 3" would be WAY to much for basically any street driven honda. i'm running 2.5 on my b16a sol and that's also too much for my car. from what i can remember, it should be 2" from turbo to i/c and then 2.25 from i/c to t/b. even when you take a look at the turbo, the compressor outlet's usually about 2" in diameter so it'll be better to stay around this size. even dsm's that make 400+ hp still use 2"/2.25" piping so a smaller displacement honda shouldn't need anything bigger. Remember, bigger is NOT always better