you2slo

If Someone had a custom tune, then added a cut out, is it necessary to retune. How much of a difference (in tuning) would the cut out make if it was open or closed? I'm guessing none??

2001NBMZ28

I'm guessing none too - I open/close mine manually all the time, then there's the electric cuout guys.

bshell

iTrader: (24)

I try and do all of my tuning with it open. I noticed with it open I tended to pick up some kr at specific rpms. By tuning with it open I can be certain that I've eliminated all kr. FWIW, I see the cutout (especially with LTs) as a sound mod and not necessarily a hp mod.

WS6FirebirdTA00

iTrader: (33)

you guessed wrong. a cutout could change a tune a lot, saw it first hand.

WS6FirebirdTA00

iTrader: (33)

if you have a shitty catback then it is a hp mod...