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DIS coil in distributor configuration?

Posted: Sat May 19, 2012 9:08 am
by pdooley
I have a distributor based ignition setup.
was wondering if I could use a DIS coil in place of the regular single tower coil?
maybe possible to ground one high tension lead from the DIS coil to the engine block and route the other lead to the center of the distributor cap?
i already have a few GM DIS coils and i need a hotter spark.

I know the better answer is convert to wasted spark, and i will do that some day.
but for now just wondering if its possible and what dwell settings to use when controlling the coil with a VB921?

Re: DIS coil in distributor configuration?

Posted: Sat May 19, 2012 2:26 pm
by pdooley
Well, in case anybody cares:
I set up the DIS coil with one tower going through a test light to ground, and the other tower to the center terminal on the distributor cap.
Hooked up the primary wires and fired it up.
Ran good for about 30 secs then died.
Determined the VB921 was dead.
No problem, I have a couple BIP373 kits, so i soldered one on.
Fired over again and it ran.
Didn't die this time, ran for about 20 minutes.
BIP was barely warm with 3.4ms running dwell.

The scope showed similar firing and burn voltages for both coils at 20kv and 2.5kv respectively, but the burn time went from 0.5ms to 1.3ms for the DIS coil.

Burn voltage seems a little low, i'm going to open the plug gap some and see if that helps.