Hard Acceleration

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jhdeval

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Okay so my car is running great and if I accelerate at a regular rate I am good but when I slam the accelerater from a dead stop the car feels very sluggish. Once it gets to about 40-50 mph it returns back to good.

Could this be a rich situation or something else?
 
There's a lot of things that could cause this. Carburetor, Basic tune up stuff. My gut feeling is Mechanical advance problem in distributor. If it was mine, I would start with a carburettor rebuild. Kit's are cheap. You could also pull the plugs and see how they look. Post pictures of the Plugs and we can look at them for you. Without more info we're just guessing but rule out the smaller stuff first. Check Plug wires, Cap, Rotor. Check for full voltage to Coil.
 
The carb is a rebuild that I bought about a year and change ago. I rebuilt it about 2 months ago because it was idling rough. I have fresh plugs and wires and cap.

The advance pot was replaced when I moved to electronic ignition distributor about a year ago. It was a new distributor.
 
Stick at least one new plug in it, jump on till it starts to smooth out then shut it of and chk the plug.
If you can take pictures of the plug new, and then after you ran it then maybe we could see what the plug says.

Just a thought.
 
just because you replaced the dizzy dosn't mean its good... and it dosn't mean it has the right curve needed... probably like 10* at idle with vacuum advance plugged, 28*-30* all in around 2500 (Mechanical adv), and then maybe another 5-10* in the vacuum advance...
 
I am not suggesting it is good simply letting people know where I am. How can I test it? I know when I was setting the timing I forgot to plug the vacuum line the first time and my advance was way high it came back down once I plugged the line.
 
I am not suggesting it is good simply letting people know where I am. How can I test it? I know when I was setting the timing I forgot to plug the vacuum line the first time and my advance was way high it came back down once I plugged the line.

disconnect the vac line and check timing at idle...

then rev the engine until you see the timing increasing, increase rpm till it stops changing... that will be your total number and rpm spec...

so total - idle gives true mechanical adv.

now for vac hook at vac tester (at idle), no pump that thing up to like 21" of vacuum(or 2 more than highest vacuum @ cruize)... this will give you vac advance number...

if there anywhere near where i said then you'll have to take it to someone with a dizzy machine and set it up for you...
 
I know when I was setting the timing I forgot to plug the vacuum line the first time and my advance was way high it came back down once I plugged the line
Just a guess at your set-up, but ported vacuum won’t cause idle speed increase at idle rpm. However, an uncapped manifold vacuum tap will increase rpm, and once idle speed has reached sufficient rpm to activate mechanical advance rpm increases still more. Stock tune mechanical advance probably starts to kick in just below 1000 rpm.
Vacuum advance “Can” has to be connected to ported vacuum, a tap located above throttle plate that only sees vacuum once throttle plate is open so it will not advance timing at curb idle rpm.
 
Just a guess at your set-up, but ported vacuum won’t cause idle speed increase at idle rpm. However, an uncapped manifold vacuum tap will increase rpm, and once idle speed has reached sufficient rpm to activate mechanical advance rpm increases still more. Stock tune mechanical advance probably starts to kick in just below 1000 rpm.
Vacuum advance “Can” has to be connected to ported vacuum, a tap located above throttle plate that only sees vacuum once throttle plate is open so it will not advance timing at curb idle rpm.

its alot higher than a 1000 rpm... before i re-curved my dizzy i had like 10* advance at 2700 and then the other spring would let another 10* go at like 4500! thats how i lost my top rings awhile back... ended up with a total of like 40 something...:wack:
 
Just a guess at your set-up, but ported vacuum won’t cause idle speed increase at idle rpm. However, an uncapped manifold vacuum tap will increase rpm, and once idle speed has reached sufficient rpm to activate mechanical advance rpm increases still more. Stock tune mechanical advance probably starts to kick in just below 1000 rpm.
Vacuum advance “Can” has to be connected to ported vacuum, a tap located above throttle plate that only sees vacuum once throttle plate is open so it will not advance timing at curb idle rpm.

I am sorry I meant my timing not advance. It has been a LONG couple of weeks.
 
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