I been thinking of upgrading my downpipe section on my Greddy Kit to net more horsepower and potential boost increase for the future. Currently everything on the car is stock aside from the bolt on Turbo Kit. I plan on converting to hondata this summer, but I want to also upgrade my downpipe section from the stock greddy downpipe to a 2.5" along with an aftermarket high flow cat such as a Catco. I have heard that a 3" downpipe on the Greddy Kits are bad for boost spiking. The exhaust on the car now, after the cat is custom 2.5" to a magnaflow muffler. Once I get it all tuned I like to keep it around 7-8psi would this be sufficent for my future plans. Also whats the peak power this could put out without having to go to 3" piping.

00 SI
Greddy Boosted