Hey how much of a gain would i get in hp and e.t. switching from edelbrock coated shorty headers, no cat., and dynomax ultra flo muffler compared to pacesetter noncoated longtubes, 2.5" dual exhaust with xpipe, and dynomax bullets. Mods consist of whats in my sig plus LT4 hotcam kit, 2.02 1.60 heads port matched with intake, and 52mm TB. Thanks

 

Putting aftermarket headers makes about 10-30 more horsepower. I would say 5 to 10 more for long tubes but it is not an exact science.

 

5-10rwhp gain is a pretty fair GUESS. On a side note, I would seriously consider getting coated headers, unless you plan on coating them yourself or something.

 

you will get a little bit more power with coated headers (not much at all but they will be cooler...)

 

Not so much for extra power as protection against rusting. I've heard on average coated headers last around 3x longer than non-coated headers. Somebody at Thuner Racing told me that once.

 

I don't know, my coated Pacesetters started rusting in less then a years time and I was told a similar thing by another vendor.