Stillen true dual exhaust

No cat-back exhaust system is going to give you higher gains than the next one... most of the power is trapped up in the cats and the y-pipe. You will be better off spending your money on these products if you are looking for more horsepower gains.

I agree, although the stock "Y" pipe is really not that bad. It's worst feature is that's it's crush bent rather than mandrel bent. However, IMO, the first change that should be made to the exhaust system is the Cats. Crawford HiFlows would be my choice. Once the cats have been changed then you can start thinking about a new exhaust system.

Lou

I agree, although the stock "Y" pipe is really not that bad. It's worst feature is that's it's crush bent rather than mandrel bent. However, IMO, the first change that should be made to the exhaust system is the Cats. Crawford HiFlows would be my choice. Once the cats have been changed then you can start thinking about a new exhaust system.

Lou

I would agree. However, IMO, the "Y" pipe is not that bad. It's worst feature is that it's crush bent rather than mandrel bent. Your first exhaust mod shoud be HiFlow cats. The stock cats are double chamber and very resrtrictive. I like the Crawfords.

Lou

If I remember correctly, it's also a heavier exhaust than the others.

Like Lou and Buddy stated, modding the cats and y-pipe is better than replacing your entire system with something that expensive. Plus, the catback system doesn't get rid of the restrictive OEM cats.

I was thinking either helix or kinetix non resonated test pipes. Any advice on those?? Sound clips would help if available.

Nobody with these test pipes??

Turbo Magazine in there Dec issue installed and tested a Stillen exhaust. They showed that the Z gained 14hp at the wheels. Stillen claimed 14-16hp, so that's not bad. Anyone know what type of gains I can expect if I go w/ the Nismo exhaust.

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I'm running the Stillen true dual exhaust and Kinetix test pipes w/resonators. Similar setups are recommended for twin turbo applications.

The Stillen is heavier and pricey...but it's all stainless and the fit is excellent. The exhaust note with the resonated test pipes is understated at all but higher rpm's.

Exhaust note without test pipes is quieter that OEM.

Unfortunately I do not have any dyno numbers to compare OEM to aftermarket.

Stick with resonated test pipes. You will be much happier sound wise