Just got my Pacesetter coated race long tubes after 2 months of waiting. On Monday a buddy of mine is going to use his companys die grinder/CNC machine to grind down all the burs and MIG welding imperfections. He says it helps the airflow by the air not tumbling at the burs etc. Anything I should look out for regarding the coating etc? Thanks for replies.

 

Unless some weld is hanging in the port it won't help much but won't hurt either.

 

They are already ported right? Deburring them will remove the coating giving rust a place to start.

 

So you're saying that it can rust from the inside out?

 

More than likely they'll rust either way. Adding a coating just slows the process down some.

 

I doubt the pacesetters are coated on the inside too.

 

If headers are cera-metallic coated, they have to be coated inside and out for the coating to do its job. You will rust (oxidize) the inside of a bare carbon steel tube just from the extreme temperature of the exhaust gasses. It will oxidize even faster if you coat only the outside of the tubes..... same affect as using header wrap, to some extent.

Grind down the welds and you increase the chances of a cracked or damaged weld, and destroy the internal coating as noted in the post above. And, some headers include a weld bead as a sort of "anti-reversion" device, limiting reversion of exhaust gasses back into the cylinders at low RPM where scavenging is low.

 

Well we die-grinded the drivers side and it is ok so far. We only grinded down maybe +-1/8" of excess weld, so no big deal either way. Also, my buddy is going to reweld around some "worm holes" in the original weld. Looks like the copper gaskets that came with the headers will be installed. The Percy's dead softs I was going to used are smaller than the header ports. Once I get the manifolds off, the size of the head port will determine the gasket I suppose...

 

Anyone had problems with the Pacesetter copper gaskets?

 

I've never had a problem with the stock manifold gaskets. You just have to snip little triangles out of each side, but I know a handful of people running them with headers and having no problems at all. No one usually likes that idea though. I would say that people will recommend something else because Pacesetters aren't known for their flange trueness.