Exhuast Questions

[Z2TT]

Hello, cars a GZ20 Soarer with a 1g-gte, got a few quick questions.

1. If I upgrade my exhuast to 3 inch turbo back for an example, will the ECU have to be retuned? I think I read somewhere that somebody modified his exhuast and he had problems with his fuel injection.

2. I currently have a huge cannon exhuast tip which is too loud, I am going to replace it with a stock muffler for the GZ20 Soarer, will this decrease performance?

Currently I think I have a 2.5" exhuast as i think the previous owner had upgraded it from stock, not sure if its turbo or cat back, have to check.

Thanks.

[Norbie]

1. No.

2. Yes, but probably not by much.

[Vios-GT_07]

1. might not be fuel injection, could be boost cut... i think it's the 1JZ or EJ20 engines that when de-restricted, make more boost (without touching the wastegate), which the ECU isn't mapped for?

2. as norbie said .. but if it's just the muffler, the performance loss is minimal at best, unless u put something like a 2 inch muffler on a 3.5 inch pipe