GM Heavy Duty Ignition or MSD 6T(6A) and HEI?

[NOVA71]

I just got a GM Heavy Duty Ignition, which is the same as MSD 6T(6A). Just wondering if anyone has had any problems using one of these with the GM HEI distributor. Someome told me that the increased voltage will melt the cap where the coil sits. Anyone had any such problems? Any info would be appreciated. I do have a good quality cap with brass terminals and an accel super coil. Thanks for any info.

[ctesla]

never heard of the old GM discharge box melting the cap, but you could put some 'buna tube' (Holley) fuel o-rings under the coil before you run the long bolts through, and snug it down on the rubber as isolators (might want to also stretch the brass spring from the center contact so you insure contact), or a light bead of silicone before setting the coil in.
this is precautionary only...
I still haven't seen any melt the cap/coil assembly, and I think that GM unit still puts out about the same amperes, and the HEI is designed for
40-60K Volts, compared to stock distributor cap.
and the Standard/Blue Streak cap is a little thicker than a stock aftermarket cap as well.
I think you'll be ok.
(still might want to carry a spare cap the first week of running her around)

[NOVA71]

Good idea with the spare cap. I will definately throw one in the trunk for awhile. I have never seen a coil melt to a cap before either and I do know a few people that run MSD 6's and have never had a proplem like that. I'll just hook it up as is, I figure it will be fine. By the way, I haven't done much in the way of messing with distributors and I know how to hook the ignition box up, but I'm not sure of the wires coming off the distributor pick up(the 2 that plug into the module). Green and white. The connector on the green wire is smaller and I think this one is the negative and the white is the positive. The wires from the ignition box are green andviolet. I think the green goes to green and violet to the white. I just want be 100% sure of this before I hook up the box. Thanks for the info.

[sub006]

I ran a Jacobs ignition with their 600-volt coil on my small-block truck for about 200,000 miles, changing the rotor and cap about every 50,000 miles.

One time after only 17,000 miles, the truck was immobilized, would crank but not fire. Turned out the rotor was burned black across the top. Never happened again, so I guess I just got a bad Accel rotor that time!

Have never had any problems with standard or high performance GM ignition parts, though.