Carb Tuning Question

[Leon]

I have a Ford 302 with a Holley carb on it and it runs all day at idle at 180-185 degrees.  At highway speeds it wants to warm up a little, but has not gone over 200 so I'm really not that worried about it.  I did decide to check the A/F ratio and found at about 2500 rpm that it is running 12.5 to 1.  (tailpipes are also black)  I know that running lean at highway speeds can cause a car to run warm, but can running this rich also do it?  I think I need to lean it out a bit, just wondering it it might help the warmup problem???  Timing is OK at about 36 degrees total advance.
Leon

[Bruce Dorsi]

Your A/F numbers are telling the truth, but the black tailpipes can be misleading.

You will see black tailpipes on many late-model EFI vehicles.   .....I've been told that the formulation of many of today's gasolines will cause the black tailpipes, even though the A/F mixtures are correct.

[Leon]

I think I found a problem - I strapped the meter to the car so I can take it on the road and test, I'm in the throttle so little because of the overdrive that I think I'm still on the idle circuit till around 80 mph.  At that speed I'm giving it a little more gas and the meter starts showing closer to 13 1/2 , still a little rich but not as bad.  If I keep it out of OD it responds a little better but it's not what it should be.  It is a 600cfm, I'm going to try a little smaller carb.