i've just me a decat uppipe of a gc8 need to get it ported before my remap. i know that i can do this myself but how much do i take out. As for the headrers i'm looking to port the om ones can i do this myself, if so how much do i port them by

Any info welcome and much appreciated

Cheers

 

The general rule I’ve always followed with my Scooby’s and other cars is the two mating parts, say the cylinder head and the manifold (headers) should have the same size openings. I appreciate that gauging the size of the exhaust ports of your cylinder head while the engine is in the car is difficult so in the past I’ve opened the manifold out to match the gasket I’m going to use. I’d be interested to know how other people gauge how much material to remove.

 

the exhaust port on the engine and the mating port on the headers are the same size!

its just the gasket that is too large and leaves the soot line that most people port to.