Headers or manifolds

[GRX]

Originally Posted by HO455

#1 tip for headers is to verify the flange sealing rings are flat and true with each other. Most manufacturers send little or no time on this. I surface mine on a 3 foot belt sander so all of the surfaces contacting the gasket are on the same plane. If there are low spots I build them up with a bead of weld and resurface the flange. On the collector end I am a big fan of cuttng the rings and flanges off and using truck bands in their place. With some exhaust sealing paste under them for a leak free seal.
Just my system, your results may vary.

^^ this x1,000, plus one more. Uneven and roughly sawed off tubes sticking through a flange does not make for good sealing. Neither does a warped flange from production process. Trip on a large belt sander can do wonders.

As for manifolds, I am a fan of using them unless your build can make use of headers. Mag articles and their sponsors are good at convincing people they are guaranteed bolt on horse power. Majority of people buying headers are getting benefit of sound only.