whats an easy was o tell if a engine is running rich or lean?

 

Soot in the tailpipe is a good indicator of rich.

 

There is ALWAYS going to be some soot in the tailpipe, especially if you have a properly functioning choke. Don't go by that.

Warm the car up and take it for a light drive then shut it off and pull a plug. Too rich and the plug will be dark brown or black and sooty. Too lean and it will be white (or damaged from detonation). A light tan color is ideal.

Another quicker method is to warm the engine up, put a towel behind a tailpipe and then smell it. If it smells like gas, it's running rich. Not as accurate, but it'll give you a quick indication.

 

Another easy way is when you start the car and if it's in a garage your eyes will start tearing. You'll know what I mean!

 

im pretty sure its running too rich theres a strong gas smell when its running but theres no leaks, and its too hard to take a plug out for that. i have to lift the engine a little to change the plugs

 

If the smell of gas is in the exhaust then you're running rich.
Is the choke working?
What type of carburetor?
Have you tried adjusting the unknown carburetor?

 

i just rebuilt the carb is a edelbrock 750cfm choke is working now im trying to tune it

 

Do you have the proper calibration kit? If not, you need it. The carb instructions give you great directions on how to properly tune the carb, but you need the proper rods and jets to actually tune it.

 

ya i have the proper stuff its just a matter of fine tunning it

 

If it's a stock 390BB then 750cfm is rather big. It can be tuned to work, but since most aftermarket carbs come factory calibrated for performance applications, a 750 will be set quite a bit differently than what you need for a mostly stock engine.