Hi 75vette, glad to see you back. You say the exhaust smells rich and you can see it, I assume you can see black smoke. It's all in the carbeuration, as long as the engine is running fairly smooth at "off idle" and on up the RPM band then the plugs are probably firing the mixture OK. Sounds like the engine builder set up the carb pretty rich, with 11.0 to 1.0 ratio you don't want to go too lean or you'll get pre-ignition but you can start leaning the carb a little at a time 'till it cleans up the exhaust. Edelbrock has tuning parts for their carbs with jets and metering rods so you can fine tune it. Find someone who has experience on that carb or call Edelbrock tech support and they may be able to get you a bit closer on the jetting.

 

Did you get the cranking problem fixed? What was the problem?

Tuning a carb is a little tricky... If you're gettin' black (rich) exhaust, you might have no more than a mis-routed, or unplugged vacuum nipple. Check them first.

First thing afterward is to remember each little turn of your idle stop screws and your jet/mix screws. ESPECIALLY IF IT'S ALREADY RUNNING.

If it is, turn the linkage screw to increase the idle speed. This is so it won't cut off as you make adjustments.

With the motor off, screw all the way in each of the primaries' mixture screws. REMEMBER EXACTLY HOW MANY TURNS YOU TURN EACH ONE. Write it down if necessary!

Back each one out one-half turn - that's a rule of thmb, I think. (Might be one whole turn, but you can go further without damaging anything).

Pull the trigger, see how well it idles. If you got black - you shouldn't at this point, but if you do (motor still runnin'), screw back ineach mixture screw about 1 eighth turn. Not one half back in, or one quarter, but half a quarter = 1/8. But again, you shouldn't at this point even have to screw IN.

If there's no black exhaust, or if it don't fire, turn each screw one eighth OUT further, to increase gas in the mix.

Once it's running again, continue backing out each screw in one eighth increments, until the idle speed begins to go down, and the black exhaust just barely becomes visible.

Then, return the linkage adjustment screw to set the proper idle speed. Leave it just a tad high, to see how well the cold start situation is. After a few drive cycles, make further idle speed adjustment.


We could begin mixture screw adjustments where you are now, but we don't know where each actually now is. Which is also why we're making note before hand.

Come back on this now, hear?