Re: Hard spot while cranking
Posted: February 25th, 2018, 8:00 am
As Viper stated, it could be the timing. My first suspect would be weak or broken springs on the centrifugal advance mechanism in the distributor or even corroded and stuck centrifugal weights. The springs control the rate at which the weights fly outwards to advance the timing. If they are weak or broken, the weights will put the timing in full advance during cranking.
On our race car engines we lock the timing out and that puts the timing in full advance at all times. For starting I program the ignition box to retard the timing 10 degrees to make starting easier and avoid kickbacks. Drag race engines essential run at wide open throttle all the time, so vacuum or centrifugal advance is not needed.
On our race car engines we lock the timing out and that puts the timing in full advance at all times. For starting I program the ignition box to retard the timing 10 degrees to make starting easier and avoid kickbacks. Drag race engines essential run at wide open throttle all the time, so vacuum or centrifugal advance is not needed.