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After replacing my valve seals eliminating all the oil that was sucking into the engine I installed new plugs and have found that #1 & #2 are running really rich - black (not wet). As you go back it appears that it things lean out to the point of #7 & #8 are really lean, I mean white with the ground strap being an ash color. The middle plugs look pretty good with a nice tan color.

This is a stock 283 internally with a Edelbrock performer manifold, one inch combo spacer and a small Holley 390 with vacuum secondaries. The car is run mostly around town with the back barrels never getting open to much. Is it normal to see this kind of mixture distribution given the setup? I'm guessing if I put new plugs in and do a blast on the highway they might look a little different. I am running bigger main jets than the carb came with, stock are 51's and I'm running 54's. This was based on my old carb (same model) that was having fuel starvation during high speed highway runs. Car runs fine no issues at all.

Thanks for any opinions your might have.
 

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Do a compression test.. a low compression cylinder will run the plugs into a black color.
Another thing that does the same is a leaking intake gasket..If the gasket is not sealed good around the head intake port it will suck in oil from the valley.

Some intakes and heads people have ported on and made the sealing surface thin.
Or the angle may not match up ..say you have angle milled heads or a used intake that was milled.

PCV valve in the valve cover directly over a squirting rocker arm. No baffle in the valve cover where the PCV valve is will do it sometimes.
Or possibly just weak oil expander or stuck oil expander

Good luck Kurt.
 
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