I know that this has been asked 10 million times but, I'm going crosseyed searching this area for an answer. I have a D15 and am not going to run high boost. I'm trying to figure out what size exhaust to run. I just don't want to do it twice. Is 2" just too small. I'm doing away with the cat because I can get away with it(no emissions). Its a 92 so just 1 O2 sensor on the manifold. I just want a little more pep and keep reliability.