4.8i Exhaust on a 3.0si?

[blndweasel]

Originally Posted by ard

wrong backpressure

^^ +1

There is considerable engineering that goes into designing an exhaust system for any vehicle. Achieving proper backpressure has an important effect on exhaust scavenging, and changes to backpressure could affect performance (negatively), emissions, and resonance. Yes, the sound will probably change. It's a subjective matter as to whether that's good or bad, but in measurable terms unless you have made flow improvements to the powerplant, you're only likely to experience negative effects on performance.

I once had a cafe racer for which I thought "I'll run open pipes, it will be cool" except it couldn't maintain idle due to lack of backpressure. I ended up having to re-engineer the pipes to add enough resistance for the engine to even behave modestly well. Compared to a stock configuration, the performance was terrible. BUT IT SOUNDED COOL. #blunderyears