Two Combustion-Related Questions

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Velocity
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Mon Aug 27, 2007 12:07 am

1) Right now, I have an automotive ignition coil. It works fine, but it is really way too bulky for my taste. The diameter is over 2", and the height is just about 6". Is there a certain (less than $20) ignition coil or product that serves the same purpose that is physically smaller than this monstrosity? If so, can you provide a link to one?

2) I hear people talking about RTV silicone now and then... I think I heard that this product was used as an electrical insulator. Is this true? If not, will regular epoxy work as an electrical insulator? Are there any other useful products which will serve this purpose?

Thanks
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homedepotpro
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Mon Aug 27, 2007 1:17 am

i know jb weld works as an insulator so i assume other epoxies will work too. 99% positive
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spudgunnerwryyyyy
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Mon Aug 27, 2007 1:18 am

Epoxy insulates great but a couple wraps of duct tape is cheap, fast and easy. One thing you can get RTV off later but once epoxy is bonded it will never come off if you need to make a repair. Sorry but I don't think auto parts stores sell much smaller ignition coils unless you can get your hands on one of the those modular coils that only powers one spark plug but is much smaller.
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mark.f
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Mon Aug 27, 2007 5:45 am

A smaller ignition coil can be found in an older outboard engine. My friend got the one for his cannon from one of these.

As for RTV silicone, it will insulate fine, but they also make "Liquid Electrical Tape" which has the same cured consistency and insulates much better.
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noname
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Mon Aug 27, 2007 10:34 am

RTV silicone has so many uses, I just keep a tube or two in my garage all the time. I've never used it for insulating (mainly because I can't do anything with electricity other than zap myself), but I think it would work.
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jimmy101
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Mon Aug 27, 2007 3:08 pm

Never tried this but it might be worth a try...

Go to the local junk yard and find a trashed new car that has an ignition coil on each sparkplug...

The coils are pretty small, much smaller than the generic auto coil.

The last I looked they are really expensive new, and you usually have to buy them in sets of 4, 6 or 8.
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Velocity
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Mon Aug 27, 2007 9:12 pm

Would something like <a href="http://cgi.ebay.com/ebaymotors/Ford-Coi ... ">these</a> work out? I'll place a bid on them later if they are still cheap
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TwitchTheAussie
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Mon Aug 27, 2007 11:27 pm

Get a pocket rocket ignition coil. Also epoxy can be removed. You just need a specialists tools; a hammer and a chisel :D
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Wed Aug 29, 2007 12:20 pm

Rmich732: Yep those are the ones, "Coil on plug" (COP). $17.50 for four (includes the shipping) would be a great price. I think a new set of 4 from Ford is more like $50~$100.

I Don't believe anyone has ever actually tried one of these coils.
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iPaintball
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Wed Aug 29, 2007 12:45 pm

You cant use a pocket rocket ignition coil, unlrss it's from a superbike, and even then I'm not sure. Regular poscket bikes use magneto ignition coils, in which a magnet on the flywheel induces current onto the coil.
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