All of the sudden my sbc stumbles sometimes when you accelerate. It feels like the engine is lacking power plus vibrating. It doesn't always do it but it ususally does it from taking off until the rpms hit 3k then it smoothens out. Sometimes it does it all the way to 5k when I shift and then smoothens out after it hits 3rd gear. Other times it won't do it at all.

At first I thought it was a plug wire that I found chaffing. I replaced it...no luck. I checked the timing and even adjusted it (14 deg BTDC at 750 rpm).....no luck.

This happened after I changed a header gasket. While doing that I also sprayed the carb with some cleaner.

I did notice that one of the plugs I removed had ashy deposits on the electrode. Not sure if that would cause it.

The engine starts fine, just trying to accelerate it seems kinda sluggish until it gets into the higher rpms.

It didn't used to do this. Any ideas whereelse I could look?

Hummm.....
Not good enough answers over at the other site Ay?

How about disassembling the carb and blowing carb cleaner through the air bleeds and such from the meetering block side?

While your at it remove the jets, powervalve and do a total-

Squirt and blow j j
Um.. this just isn't going to sound right if I finnish this sentence :D

You know what I mean anyways ;)

I'm compiling as much info as possible.

I think I know what you mean...possible carbureation problem.

I was having the same problem. I changed one of the plug wires that was bad an adjusted my accelerator pump and the problem went away for 3 days.Yesterday I was cruising the car and it was running great until I was coming home an ran over a sewage drain in the road and it started doing the stumble thing again.I'm going to check all the plugs and wires to be sure that's not the problem. I also suspected bad gas at one time.

After you get done with cleaning the bleeds on the carb,put in a new set of plugs if you have one that's fouled out it won't run right till you replace them.

had a problum like it befor . if you can try a coil from another car and se if that fixes it .if so your coil is braking down

That does happen.Especially if your coil is sitting in the stock position on top of the manifold.

Better off with it mounted horizontal on the firewall.