Which cat backs add the most horsepower/torque? is Borla T-304 S-S Catback any good?

 

NO not even close! That was my third exhaust system of the five I've had on my coupe, the way it's made and the sound sucks. The only positive is that it was a true-dual cat back system. HKS, Stillen and MotorDyne all make great cat-back systems that are well made and sound good....plus offering HP gains. Two of the five systems I've had on my coupe have been sponsored and I sold those in favor of my HKS dual/polished system....
Gary

 

I ordered the hks hi power dual exhaust i'll be putting up before n after videos of how she's sounding...stillen headers getting installed at the same time...now I'm looking for some spacers...which brand do you think gives the most gains?

 

motordyne spacers are awesome

 

You'd be major $ ahead by getting HFC's rather than headers because most of the restriction in the exhaust system is in the OE cats. Berks HFC's offer an increase of 10 RWHP while headers will only give you 3 to 5 HP along with being a PIA to install. The best spacer is the MotorDyne 5/16" and available from Riverside Infiniti 800-913-3130 ask for Tony in parts.
Gary

 

Sorry to HiJack but would a CatBack System (Invidia Gemini specifically) remove the Catalyic Converter? I'm incredibly uninformed about the whole exhaust systems. I am tryna get the Invidia but wanted to know if I would have any legal problems Sorry again!