I just joined after 12 years with DSMs and was wondering if anyone has used two and a

half or three inch pipes for their exhaust systems. I heard with some engines large pipes

affect performance. Would that be true with the CL Type S? I was thinking of going larger

with a larger catalytic converter.

 

The CL exhuast system was designed to be very free-flowing from the factory. On a N/A CL-S doing a full cat-back exhuast may give you only a few hp. The only time where the exhaust shows real gains is when you go FI.

On the other hand, the exhuast note could be better. I'm envious of the G's and their sick exhuast sound, where ours are rather quiet, but for a sleeper that could be good.

 

, except for headers, which have proven to have been engineered extremely restrictive. A high-flow CAT will also help a bit, IIRC. But the B-pipe back won't get much better for NA.

 

Intake will add 8-12 whp
Headers will add 25-30 whp
Cat-back exhaust will add 8-10 whp on N/A, cloer to 12-15 whp on a boosted CLS