ground stock header

[dempsey400]

I've read alot about people grinding their stock header. How much difference would this make. Where are the welds? Are they around the flanges on the head side? I have a 400 with a wb e series slip on and k&n and dynojet kit. thanks

it prolly doesnt help much but what ever u can get. they are close to the flanges where u bolt it on the head.