On another forum I picked up a reference to supplying a coil with a higher than normal voltage, say 18-20V, presumably fed through the electronic module first using a booster DC converter (or even a 6V battery in series for a short while) with a standard inductance type ignition system. Has anyone here have any experience with this? The long and powerful spark which would result (if it works) would help to push the cruise lean burn envelope, which is my intention.
I intend to use a Pertronix Ignitor II and would like to know how much voltage this unit can safely handle, also any other experience/warnings would be appreciated. I searched the archives but couldn't find anything relevant.

If you go to DUI or performance distributors the have a product called the minivp which ramps up the volts to 18 just to the ignition. It looks to be very interesting and I am thinking of getting one myself. I'm currently using their street/strip hei distributor and I'm happy with it and there customer service. Good Luck

Just from my point of view, I don`t see how this would do any good. You can give a ignition system all the volts you want along with amperage and it won`t make any more power than it did with a stock HEI. Increasing fuel and air make more power, give it the proper spark at the proper time and you`ve got a winner.

I see your point about there being no advantage, but I should have added that I intended to take advantage of the increased energy by substantially increasing the spark plug gap, to be able to light off very lean mixtures in the range of 17-19 AFR.

I just picked up an Accell unit for $56 new. It does the same thing as the mini VIP but only above 3000rpm. I figure it can't hurt for boosted applications and 3000rpm happens to be where my turbo makes full boost. Also because the accell unit only activates above 3000rpm it should save the coil some.

I've done it with an hei it works well.But there are drawbacks if you have the switch on for any length of time without the engine running you will fry the module.We used it in a restricted circle class that didn't allow an msd it allowed larger gaps up to a point then you hit wire leakage.The main advantage was it extended the rpm range of the stock module higher without missfire.

I doubt you need 18 volts for a properly working ignition system. The spark voltage is dictated by the gap and any excess voltage is taken up by resistance elsewhere.....wires, etc. The spark may last longer,, so more energy, but you should already have enough with a properly wroking system.

As far as using 18 volts with a non-points dist, it probably won't burn out any electronics, but I would go to the manufacturer's web-site and stick within their supply voltage specs. If it's stock EI, then maybe try it with another unit from the junkyard first.

The only reference I heard about using 18 volts was for track cars that ran without an alternator. A partially discharged 18 volts battery (or a 12 and a 6 in series) is still over 12 volts where the 12 volts battery may discharge to the point the igntion starts to misfire.

If you want current to light a gap get a magneto.

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Outlawed tunes from outlawed pipes

What you are wanting to do is the original reason the msd system was conceived in the early 70's.I suspect you are trying to get really good mileage for cruising from the question if so msd style system would probably be the way to go.The multiple sparks in the cruising rpm range would give the lean mixture a better chance to ignite.