250 with HEI Questions

[G8rN@te61]

I had been posting questions in a different model thread I found so I thought I would bring it back to this Model year forum even though my engine is 250 out of a '71 camaro put into my '61 step side. Good ole google has provided me with more questions than answers....

I installed an offy intake, 12bolt dual headers to porter mufflers, an Edelbrock 1404 500cfm carb, and an assault racing 50kvolt HEI and wires. Compression for all cylinders was ~120 -125 which is pretty good since factory is 130. 3speed saginaw.

Truck runs great! Starts right up. Way smoother, no stalling, and no pinging whatsoever. Sounds great! However, I noticed that its now spitting some black soot out and thus probably running rich. Smokes a little too.

I turned the mixture screws 1/4 turn clockwise (leaner) on the carb, I also bumped the timing up to 10 and gapped my NGK UR4 plugs to .6 which is in the middle of the recommendations of .45 to as high as .8(Langdon).

#3 plug is really black which I understand is common on IL6's so should I go with a different plug or gap? Other plugs seem to look good. Brownish and clean. I might need to tighten the manifold bolts i've read.

Is there a better plug to use since I am modded? Go hotter?

Should I increase the timing to 18 which Langdon recommends?

I tried the relay trick for the HEI but I have since read that is a waste since the amperage draw is so low at 2amps and I only see a .5 volt max difference across the relay. Intermittently it won't turn off either. Its a cheap relay from Oreillys so I could buy a Bosch one and try that. I am probably going to go back to just hooking it up to the solenoid output since my electrical system doesn't have that resistor wire connection like 67's plus do.

Thoughts and suggestions?

Thanks,
Nate