Thread: tuning and timing questions???

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Don't go to the trouble of pulling the timing cover until you get the other stuff squared away.
Right, now, a cam off a tooth is a possibility, but do the easy stuff first.

If you're familiar with cams etc., you can check to see if it's installed properly by finding true top dead center and using a degree wheel and dial indicator.
A subject for another time, but in case every thing else checks out....

Like Skids said, make sure your accellerator pump adjustment is correct.

Looking from here, I don't think the carb is your problem.
More than likely a timing issue.

There's a lot of confusion about how vacuum advance works and where it comes in at.

The basics are, mechanical - or centrifugal as some call it - responds to engine rpm only.

Vacuum advance responds to load - or vacuum level which is lower when the engine is under load.

Ported vacuum operates similar to manifold vacuum, but ported is at zero at idle, 10" or so in the mid-range under light load and back to zero at full throttle.
Vacuum advance does not stack up the advance as rpm comes up whether selected to ported or vacuum unless the engine is running with no load and above the idle rpm.
It can help to think of a vacuum advance cannister as a vacuum retard device.

Double check the plug wire firing order.
An easy mistake to make and double checking is a good idea.

So if everything is correct, you nail the throttle, the vacuum advance drops out and you're running on mechanical advance only as the engine rpm comes up and you're 'all-in' at 2200-2800 rpm or wherever in the curve you set up the 'all-in' point.

Basically, you don't want a drag racing advance curve in a street driven car.

Looking from here, it looks very much like the distributor is a tooth off.
Get the engine up on TDC - Top Dead Center - on the firing cycle with both intake and exhaust valves closed.

Install the distributor so the engine will fire at that point.
Make sure you haven't set things up so distributor rotation is limited.

Disconnect and plug the vacuum advance line at the distributor so there's no vacuum leakage from the manifold.
A golf tee makes a great plug.

Start the engine, set the initial timing with a light and if everything is working right it should run ok.

Install the vacuum advance line and you should see or hear the engine rpm increase a couple hundred rpm at idle.

Don't sweat it if you run the engine up to 1500-2000 rpm with no load and see the advance as high as 45-50 degrees BTDC.
Doesn't hurt and in fact is what you want.
The extra timing advance is required to give the lean idle mixture time to burn.

Do you have a PCV setup on the engine?
If a PCV valve hangs up it can create a major hesitation coming off idle.