Porting headers?

[Birdie2000]

Has anyone here ported a set of headers at the flange to clean up the welds inside the tubes? I know this obviously varies from header to header, but if you have, did you typically add material via welding on the outside of the tube/flange, or did you just grind down the welds inside and try not to break through? Just wondering because it looks like I could just grind them as they are now without breaking through, but I wonder if that would cause the header to crack in that area since it'll be thinner.

Mainly just curious if anyone's done this and had the header tube crack at the flange before. The welds inside the tubes are obstructing the exhaust flow. The flange opening is correct for the exhaust port, but the weld narrows this down a fair amount.

 

[daveg]

I work on the LS7 exhaust manifold line at work. They are all hand ported/blended at the flange. Its possible, just be careful

 

[Sean]

Honestly if it doesn't overhang the port, I wouldn't sweat it much.

 

[Birdie2000]

Honestly if it doesn't overhang the port, I wouldn't sweat it much.

From what I can tell from mocking up the gasket against the head and then against the header, it does.

 

[LT1Pat]

Just clean it up enough that there is no lip entering the exhaust.

From what I can tell from mocking up the gasket against the head and then against the header, it does.

 

[vector006]

Agree, just knock off sharp overhanging edges and blend it gently. You wont gain anything noticeable by porting it...