Looking for advice. Having problems with 1970 Coougar w/351c. It is hard
to start and uses lots of gas (<9.something mpg in city, used to 12 or so).
When strarting cold, it appears to flood easy as you can smell gas at tail
pipe. Recently put kit in carb trying to fix this and found float orings
pretty much gone (crumbled when removing) but can't say much improved.

Changing the plugs helps with the starting for a while but not long. Pulled
plugs and the front 4 (1, 2, 5 and 6) are black with soot but other 4 are
ok. This is after about 500 miles on new plugs. The motor was rebuilt
about 10 years ago with a used alum edlebrock dual plane intake and 600 cmf
Holley 4bbl. There are no vacuum leaks to the outside along the intake to
head seams. Don't think there are any other vacuum leaks.

What would cause the front 4 plugs to run rich but the back 4 be OK? I'm
99% sure cylinders 1,2,5 and 6 are not on the same side of the dual plane
intake so does that elimnate the carb having a problem left to right? I'm
tempted to get a new carb but would like some confidence that will solve the
problem. Since the carb rebuild, there is a flat spot in the throttle when
you accelerate hard. Probably just the accel pump not set right but maybe
another symptom.

Any advice appreciated. I will try to post pictures of the 8 plugs later.
thanks, bobby
bbusselmanCoyote at hotmail dot com (remove the dog to send email)