duraspark HEI conversion question

I'm of course talking about the conversion where you wire a GM HEI module inplace of the duraspark box with an 85 distributor. I know how to wire it and all, my question has to do with where to mount the module. I have an old PII heatsink and an aluminum bracket I fabbed up to mount it but I am wondering if I should have any concerns about moisture or if the length of wire between the module and the distributor will affect performance.

All the electrical in my engine compartment is hidden in the driver side fender and I plan to mount the module in there as well. The wiring will run through the cowel and through a grommet in the firewall to the distributor so it will probably be about 5 or 6 feet long. I imagine it will be possible for some water to get in there when it rains or when I wash the car so could this be an issue?

Well then I guess the length of wire shouldnt be too much of an issue? What about mounting it out in the elements? I really want to mount it out by the coil, not in the cab.

Maybe you can answer another question for me.... I just got my 85 distributor today and when I compared it to the original one I noticed that the shaft was shorter. Im talking about where it extends down from the gear and engages the pump rod. The original was abot 1.5" and the new one is only 1". All other dimensions are correct but I have concern that it wont grab the pump rod enough. Did you run into this or do I have the wrong distributor?

double post

dastang2 said:

yes you can use that, i beleive that the pump's rod goes further into the tfi dizzy than the duraspark one. you can run that hei under the hood, but for heat reasons i put mine inside

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I dont really think heat should be an issue. If you think about it, those modules are mounted inside the cap on the GM HEI with no air circulation and they are fine. Im mounting it sandwiched between a piece of aluminum channel and a huge heatsink. The heat dissipation should be far better than the stock GM setup.

I think I might stick some clay in the shaft and then stab it in to see how far it is going in there. Just from looking at it I would say its only about 3/8" to 7/16"