Well, today I am going to pick up a Gibson 3"/3" muffler and a 3" manual cutout from a member on these boards. My question is, while I'm still running a stock tune and just intake/exhaust would having the cutout open at the track hurt my ET's compared to running through the Gibson? If so I'll just use it to wake up the neighbors before school

 

you'll notice a loss of bottom end but you'll gain quite abit on the top, at least I did. mine is a dog anyway with 3.42's... my gear swap should help it out a lot. I have dual cutouts behind the headers, there are pics in the link in my sig...

 

That's what I figured. I plan to swap in a 3.73 or 4.10 gear later and a CAI which will helpfully put the power back up.

 

when i was on totally factory exhaust, i gained alot of bottom end with the cutout open. ive never tested the longtubes+open cutout VS. the lt's and muffler...i just look at everyone elses success with open cutouts on the track