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So got her running. But alot of backfiring out the carb. When i put my foot into it it hesitates and sucks and pops then catches up to itself. Also feels like she not going anywhere when i get on it. And ideas. Its a holley 750, msd ready to run dizzy and a edlebrock high rise intake.. All imput much oblidged
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That is characteristic of ignition / timing problems. Make absolutely sure that your plug wires go to the cylinder they should. Also, make sure the timing is in the positive range: before top dead center. Clevelands timing marks can be way off and Clevelands like lots of advance. I am running about 30 degress BTDC static timing at idle.
Do you experience any "Popping", "Hesitation" above 2,000 rpm?


The reason I ask is because a faulty accelerator pump can cause "Stalling" upon initial "Stepping on the pedal".

Once the carburetor is beyond the initial squirt of gas ( accelerator pump) the engine relies on vacuum through the carb to fuel the engine's needs.

Also, Do you have a fuel pressure gauge?

Do you know if your carburetor is getting enough fuel?

Does your Holley have a clear fuel bowl site window?...Mark
Do you have full fuel bowls during the hesitation?

Trying to neither determine a fuel starvation situation or eliminating that from a possibility.

I can't recall where I heard this quote..." 99% of carb problems are electrical".

Your distributor isn't installed 180 degrees off is it?

Is number 1 cylinder on the engine getting number 1 on the rotor/distributor cap?...Mark
quote:
Everyonce and a while i will get a flame burst through the carb


I know it's been often said, but... Check that distributor shear pin. (maybe check the "basics" first, but...)

My pin had not failed completely, but I would set the static timing (16*), and then it was good at idle, but retard under engine operation.

When the pin was first starting to go bad, I would get backfires on deceleration when I let off the gas.

When it was near death, my symptoms sounded a lot like yours.

Good Luck.

Rocky

PS> I agree with Mark that people are often thinking carb problems, when it is due to ignition issues. I did that....
quote:
Originally posted by Bumblebee13:
Im sorry.. My original dizzy was a dual point. I could not get it to spark. Even with lots of time working with the points. So the guy at the pantera shop suggested the ready to run msd



You were saying earlier the car ran ok with the original parts.

If that was the case what distributor were you using before you put the MSD dissy in ??



"Ok have a 72L with stock motor. Have edelbrock manifold, holley carb, msd ready to run dizzy and hall exhaust. Just tonite i got it started and it fired right up but now i has a slight pop on the driver side of the exhaust. And when i raise the rpms it let out a puff out of the carb. I have my timming set at 10 degrees. It ran fine before when it had all stock parts. "
quote:
Originally posted by Bumblebee13:
Im sorry.. My original dizzy was a dual point. I could not get it to spark. Even with lots of time working with the points. So the guy at the pantera shop suggested the ready to run msd


Can you find a Speed shop with a distributor machine that can install & set the points/gap/dwell & total advance on the dual point distributor?...Mark

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