carb issues

OK, I'm not a carb guy at all.. just for some info. My problem is that between 1500 and 2500 rpms I have no power. I can't even make it up hills without over revving my truck to the point that my clutch gets smelly. I rebuilt my engine two years ago and did a transmission swap and an aluminum drive shaft conversion. So I do have some knowledge. When I did it two years ago, man did it have power. But sense then I moved to NY from Seattle and towed about 2000 pounds all the way here. So I have tired this little puppy out.

So not having power between 1500 to 2500, my other symptoms are that it backfires when my foot is off the gas. Backfires when I have the clutch Half compressed around corners. Also, it has no acceleration.

I have checked my timing (OK), clogged cat (OK), volts to MSD (OK), spark plugs (OK), some leaks around carb, and intake. So I will start there.

But I still think that it's a carb issue but I don't know where to start with that.

Do you guys have any ideas on what it might be in the carb (32/36 Weber) and how to fix it? Also where to look.

OK, so today I sealed my intake with RV sealant, just to diagnose my problem quickly. Also I sealed some other things on the carb. (What I did was took off the top part of the carb and took out the gasket and used RV sealant. Also did that at the diaphragm.)

The symptoms are still there. So does anybody have any ideas? Please.... I am stumped. Thanks

how many miles on the truck? have you ever had it rebuilt? after time everything starts to fall apart... maybe its time for a rebuild.... mine is at 180k miles and im starting to notice a loss in power (not that there was ever any there lol)....

Well, I think that it has about 15,000 miles on it. I rebuilt it two years ago. Bored it 20 thousands over, 272 cam, MSD, total seal rings, transmission conversion, aluminum drive shaft conversion, headers, Weber 32/36, blah..blah..blah. LOL

It started to act up after I drove 3400 mile to NY. I blow out my cat (fried the inside of it from exhaust being so hot). Then the little stuff start to happen. Loss of power, no/ low acceleration, now no power between 1500 and 2500 rpms. I'm leaning towards carb. Had problems from the start with this carb. Idling problems, the sputtering, the usual for conversion problems. For me anyways.

But I'm stumped. Need super duper help from the B-Scene.

So today I went out to take a look at my carb to see if maybe I did something wrong when I put on the Weber. I found this diagram and it looks like I have the vacuum advanced switched on the side that EGR valve. The vacuum advanced plugged because I took out the EGR Valve.


Does anyone have it swapped like me or do you guys have it like the diagram? I thought you are suppose to have no or very little vacuum at idle and more when you accelerate. The one on the left (EGR side) has little or no vacuum. The other has a lot more vacuum. So which is it left or right?

Can you guys put up some pics to help me out.

plug the one on the left and vacuum line goes from the one on the right to the dizzy.

OK, I'll try that. But I'm still wondering how much vacuum are you suppose to have for the vacuum advanced? Or is that a silly question? Does any body know?

Aren't you supposed to have low vacuum at idle and more at acceleration?