NDN4VET

I have a 97 c5 base coupe black on black with tinted glass t top with borla exhaust mufflers.
Since it is illegal to do motor mods in calif. I've tried to think of legal was to improve horsepower and performance. The local corvette shop in San diego suggested purchasing the exhaust system from a c6 zo6 (exhaust manifolds h pipe and cats).
Had them installed the other day, my oh my what a difference. I've read that I should pick up about 20 horse power, well it certainly feels ever bit of that, but to me one of the biggest differences is the way the car just feels and sounds, I had kinda of drone with the original borla mufflers and stock exhaust, and the car would vibrate some when I really got on it. Now it's just smoothed every thing out and it performs like a whole new car, my experience has been great. The car is just breathing way better, next I plan on installing Callaway honker intake, hope to get another 10 horsepower.

Time for a C-5

Plan a tune after after the cold air to optimize everything. Plenty of people rave about the benefits of the $150 ECS mail order tune.

Dbl_D718

Just to be clear, installing the C6 system is still technically not CARB legal. You will probably manage to pass inspection since the parts look stock, just don't tell the shop about your clever modifications thinking that you are within the law.

z06sicz

So you bolted up c6 z06 cast exhaust manifolds, z06 h-pipe, and used a c5 rear section??

sirdano

I really doubt any performance gain from the stock z06 parts. I put shorty headers on my 98 and it added very little

NDN4VET

C6 zo6 exhaust manifold, c6 zo6 h pipe,c6 zo6 cats. With borla exhaust. Noticeable improvement in sound (no more drone) and feel (the car accelerates better, less vibration) also I know it's not a lot but certainly a horsepower improvement.

NDN4VET

Well aware of the fact it's not "within the law" Before I did it I talked to others who have made the same mod and have passed smog on 2 different occasions, also talked to my smog guy and he said, "who would know" its stock corvette equipment. Most smog guys or for that matter most people don't know the difference between one exhaust or the other.