header coating discolored

[TBART70]

Every tube at the first bend, I think it's from heat/high temp. It is not rich or lean, runs well, no full exhaust on car yet. Made some changes, different air cleaner , smaller spacer for carb 1" to 1/2". Headers are 1 3/4" used to be 1 5/8". Not timed to full spec at the moment, 32*.

406 sbc dart iron heads



thanks for any help

[71RS/SS396]

3 things cause that; To lean, retarded timing with an overly rich mixture ( especially on forced induction engines ), or cheap coating.

[TBART70]

Heddmen headers, coating looks good. They are going to recoat them. I am going to put the timing up to 35-36*, it doesn't seem overly rich but it is hard to tell when driving. This motor was in my car and now in my buddy's Chevelle. I never had an issue with it being rich in my car, it was in there for over five years and no fouled plugs.

thanks

[tommycomfort]

My Hooker LS headers are the same way. I am possitive the timing and fuel mixture is correct... Might step up to a Jet-Hot coating this winter.
Tom

[analyte]

Heddmen headers, coating looks good. They are going to recoat them. I am going to put the timing up to 35-36*, it doesn't seem overly rich but it is hard to tell when driving. This motor was in my car and now in my buddy's Chevelle. I never had an issue with it being rich in my car, it was in there for over five years and no fouled plugs.

thanks

How much initial timing? I've found that too little initial will cause a lean condition due to the cam appearing to be retarded versus where it should be. I chased this issue for months on my old big block. It would run hot at cruise so I spent dollars on an alum radiator and elec fan, plus changing every jet in the carb thinking it was lean.

I ended up finding out my 288/296 cam was installed at at 10deg BTDC and it wanted to be 18deg BTDC. After setting the initial correctly, all my problems went away. This might not be your problem, but I just wanted to throw it out there.