dump pipe ??

[Shimy87]

Would there be any gain from a dump pipe on a stock GN with basic upgrades? I saw this cool electric butterfly valve for exhaust on the show "Gears" and it got me thinking. I like the sound of my flowmaster exhaust but as I've read here they suck for performance on these cars. I could put a y in the pipe before the connection to the gutted cat and put this valve on the end of the y. When I want to run at the track ( or at a light) I could just flip the switch.

[SuperSix]

I couldn't HURT - But I don't know if the gains are worth the $$$. It would definitely sound cooler. 

[Just a Six?]

I used one for years but without a cat to start the testing from so any gain was minimal. They can be adjusted from quiet to loud while driving which is sorta cool. I sold my setup a couple years ago & run a high flow cat as I wanted my car quieter. It was fun for a while but more of a toy than anything for me.

[Steve Wood]

I would expect zero gain if you are making less than say 450-500 hp with a 2.5" system.

Also, they are very inefficient if they are the offset, side exit as the exhaust flow tries to maintain the straight line of flow unless there is a lot of back pressure due to restrictive mufflers, etc.

[larrym]

With a hooker 2.5 down pipe and crappy 2.5 turbo muffs I went from 380hp to 420 hp on the dyno. Doesn't do much with a good exhaust system, don't use it now with the 3" down pipe and "cough" thrush glass pack "cough cough" Hill Billy Deluxe!