MOPAROFFICIAL
Oogliboogli
He could have a valve hung open and still crank that much and more.
New motor, check the pushrod length,
Swap wires, plugs....valves hung open
Diagnosing cylinder misfire
- Thread starter Penstarpurist
- Start date
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New motor, check the pushrod length,
Swap wires, plugs....valves hung open
Dana67,
Having the dwell reduce with vac adv applied is good. Vac adv applied means cruise, which is low-med rpm where low dwell is better, because extra dwell is not needed & the coil runs cooler. High dwell is only needed for high rpm, to extend the charging time for the coil. The variable dwell of the GM HEI is one of the reasons it is such a good ign system: it keeps dwell low at lower rpms & extends dwell at high rpm where it is needed.
Having the dwell reduce with vac adv applied is good. Vac adv applied means cruise, which is low-med rpm where low dwell is better, because extra dwell is not needed & the coil runs cooler. High dwell is only needed for high rpm, to extend the charging time for the coil. The variable dwell of the GM HEI is one of the reasons it is such a good ign system: it keeps dwell low at lower rpms & extends dwell at high rpm where it is needed.
Penstarpurist
Well-Known Member
Okay, we swapped out the plugs. Fired right up. Running strong again, then shut down on its own. Would crank but not start up. Swapped out the ballast resistor that was already new just a few days before. Anyway after swapping it out, fired right up and runs strong. Set the initial timing on it and idles great, nice throttle response. Something is knocking the ballast resistor out randomly and frequently. Haven’t even got it out of the shop yet and it’s gone through three resistors. The brand is “standard” or stp. May have to try a better brand, it didn’t want to start on an msd resistor. At least getting it to run strong.
Have you tested the ballast resistors you have removed? Would be interested to see if they are really bad, or are you chasing a bad connection issue.
Coil. Smp ballast resistors usually dont fail two in a row.
Penstarpurist
Well-Known Member
Haven’t tested the ballast resistors that we took off, not that it would mean much but the coil was replaced a few days ago. But could certainly be bad out of the box. My son just tested the voltage regulator and it’s showing that it’s putting out 15.5 volts on a fully charged battery. And there again the voltage regulator was replaced at the same time as the coil and resistor. But if it’s putting out that kind of voltage we’re leaning towards that as the culprit.
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