Anyone gutted their main cats? I've got a friend that did it on his R33 GTS-T but with his high flow cat not factory cat. The reason I'm asking is I want to get my full exhaust done asap but just wondering if I needed a high flow cat or just gut my stocker and just get a new catback and dowpipe(works out cheaper:p). Will I need an ecu becuase once it's gutted would it'll act like a midpipe?

 

Buy a midpipe and do it properly. They can be found for like $100. You will have boost creep with a gutted car, and will not get the full performance benefits. Basically, you get what you pay for

 

So it'll still creep, I'll just get a high flow and do it properly. I don't really want a midpipe because I'm short of cash for porting wastegates and getting an ecu so the exhaust is the only mod I want for now. I've quoted around for custom full exhuast(w/hf cat), they said around $800-1000AU and I went to an import shop for japanese full exhaust they quoted $2000AU+(cat alone is $1000AU!) because of the different/lighter materials and the perfect flow or something. Maybe they just want to make cash off me. What are the benefits of getting a japanese exhuast system? BTW the brand is Fujitsubo.

 

I have a downpipe, gutted cat, and stock catback. I had a very desirable boost pattern (non-seq) , it was 10psi until about 6.5k where it would creep to 10.5 psi then finish at 11psi barely. Perfect and gave me the power I wanted with a stock ECU. I dont use **** 91 octane though, I stuck with 93, 100% of the time.