On my 83 camaro 66k mile 2.8 v6 5 speed, it has an issue between 1k-2500 rpm where the engine stutters while driving. Recently rebuilt the carb (varajet). New spark plugs and wires. In neutral and anywhere above 2500 rpm the engine runs fine, part throttle or w.o.t. But in that range, the best way I can explain the feeling is if you were to punch the throttle and let off three or four times real fast. It isn't clutch slippage causing this. Any help would be greatly appreciated!

 

I'm thinking you're more likely to get help from the V6 guys than the Carburetor forum guys.

 

First obvious question is did this all happen prior to the carburetor rebuild and new plugs and wires?

 

Yes, did the exact same thing. I've had some people tell me it's a vacuum leak, others tell me it's carb related.

 

If you are absolutely sure that the carb was rebuilt correctly, then it could in fact be vacuum, or even timing related. If you use the process of elimination, you will eventually find the culprit. Be sure your coil and ignition module are in good working condition. First, pull the EST bypass and confirm your base timing is correct. If it is, then re-connect the EST bypass wire. Pull the plugs, make sure they are gapped correctly, check the wires and make sure they are not arcing meaning check for any cuts in them and be sure the firing order is correct. If this doesn't take care of it, then let the engine idle, and lightly spray carb cleaner with the engine idling in key areas to check for any vacuum leaks. If you have no vacuum leaks, then move on to the carb's choke setting and accelerator pump...

 

I found two vacuum lines that were not hooked up completely. Fixed that and the issue improved significantlt but it is still there but only right around 1500 rpm. Plugs are gapped right and firing order is correct. I have no way of checking timing.