HEI module dwell time.

[Ricko1966]

Many times I've told people on here that to the best of my knowledge only GM and NAPA premium ignition modules vary dwell. Some of you realize it's important,some are like WTF is he talking about. I just stumbled across an article explaining dwell and ignition modules and how to check. Something this article doesn't cover,or I skimmed it too quick and missed it it,. Dwell is the amount of on vs. off time on the coil and module,too much on time is going to cause modules and coils to fail early due to excessive heat.

Saturation Time: Checking GM HEI module dwell. - Farm Machinery Digest

In 1975, General Motors, thru their Delco Electronics Division, completely rethought how an ignition coil was controlled. This was accomplished…

farmmachinerydigest.com

 

[Turbo4whl]

Interesting read Rick. As you might remember GM called out 28-32 degrees of dwell on the 8 cylinder, point distributor. I was taught to try for closer to 28 degrees because as the rubbing block wears, the dwell increases. The change in dwell also effects the timing. So always set dwell first, then check timing.

@Rusty Nail Hey Rusty, Rick said "dwell"

Hey, who knows what point float is?

 

[Ricko1966]

Interesting read Rick. As you might remember GM called out 28-32 degrees of dwell on the 8 cylinder, point distributor. I was taught to try for closer to 28 degrees because as the rubbing block wears, the dwell increases. The change in dwell also effects the timing. So always set dwell first, then check timing.

@Rusty Nail Hey Rusty, Rick said "dwell"

Hey, who knows what point float is?

Another neat trick was run a dual point distributor wired to a toggle switch,set dwell different between the 2, flip the switch to run on one or the other to gain or lose a couple degrees of timing. Before they had Knock sensors.