Is it possible I'm getting spark blowout of a 10.7:1 350 motor?

My exhaust has always smelled pig rich at idle, no matter how much I messed with the idle screws.

I took the car to 4000RPM the other day and some guys from work told me I was blowing black smoke the entire time.

I've been having trouble getting the car to get good gas milage....so maybe it's just an ignition problem. Everything is brand new, from the coil, to the distributor, to the moroso 8mm wires. I'm running the R42LTS Delco plug for Vortec heads. Someone suggested I move up to a hotter plug for a better burn.

 

I am guessing you have a huge carb for a 350 like a 750 with the stock jetting. Pull some jets out of it and lean it out some. Also make sure the timing is right. You should not get leaks out of the spark plugs and I don't think that changing to a different plug will help you.

 

My sig has my motor buildup. It's a 670 Holley Street Avenger. I believe is has 68/72 jets.