I have a tunnel ram with 2 Holley 750 DP carbs on my 505 inch motor. I put a set of spark plugs in and took the car out and drove it all day. The car ran okay for the most part, it dose not idle very well in gear. Anyway I pulled the plugs and noticed that the front of the motor
(plugs 1,2,3 & 4) are running lean and the back plugs are running rich. The carbs are set up exactly the same. When the motor is warm I turn in the mixture screws in until the motor stumbles and then I back them out ½ turn. What would cause this? Is this common? Should I just back out the mixture screws some more on the front carb and turn them in on the back?
Thanks.