I have found a cat-back exhaust made by Hotshot. It is 2.5" piping and I think that is too big for my N/A motor with very little bolt ons. I know the greddy is 2.3XX", does anyone have the HS cat-back? Is 2.5" too big? any info/input would be greatly appreciated

ttt

2.5 is a little too large. I think that it is for if you have their turbo kits. You want one arond 2.25 inches.

I thought so too but greddy is like 2.326 or something like that so its only .15 or so bigger, and its only 320 shipped.. I do think its a little too large though myself..just wondering what other people thought

I have a GReddy BL. The Hotshot intriges me though. I am looking for a 2.5 exhaust. I plan on maybe going for Nitrous in the future.

Here is a chart from a company called Donaldson in Australia that has experience with making exhaust systems for turbo trucks.
Based on 2psi of backpressure, using a gasoline engine, (four stroke). Numbers on the left coincide with your horsepower figures and the right represent reccommended sizing for exhaust:
100.5HP/2" (51mm) diameter
160.8HP/2.5" (64mm)
221.1HP/3" (76mm)
308.2HP/3.5" (89mm)
502.5HP/4" (102mm)

I believe the power rating is coming from the Crank HP rather than the WHP. The source is 21st Centruy Performance by Julian Edgar.

I haven't tested any exhaust systems though, so someone may be able to reccommend the perfect set-up. I have been happy with the GReddy, but I feel I can gain more in the top end with a more open exhaust. We shall see.

http://www.se-r.net/header_exhaust/general.html

The answer to all questions. Too bad Merlins sheet isn't still up.

Originally posted by Pretty White
http://www.se-r.net/header_exhaust/general.html

The answer to all questions. Too bad Merlins sheet isn't still up.

Thanks but that really doesnt help at all.. It says nothing about the 2.5" system or even the greddy or hks which is 2.3XX".. they only talked about 2.25".. thanks anyway