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> Crankfire, over simplified?
Sparky
post Aug 16 2005, 11:22 AM
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Ok so I like my carbs and I thought hmm wouldn't it be neat if I could hook up a crankfire system. I mean really I've got the msd installed, so whats next? I need a magnet set on the flywheel a magnetic pickup on the fan housing and a coil pack right? Wont the MSD handle the coil switching? I dont want to go full blown Megasquirt or anything like that just want crankfire with the carbs. I have a buddy who was going to design one for me but he still has a couple of tug boat diesels ahead of me and it looks like it may be awhile.

Thoughts? Can of Worms?

Mike D.
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tat2dphreak
post Aug 16 2005, 11:30 AM
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I think others have done this with the trigger/sensor on the front of the engine, not the fly. but, I think it can be done...

go for it, do a step-by step, I would love to do this instead of a dizzy
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olav
post Aug 16 2005, 11:33 AM
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My Electromotive crank fire on the front of the engine. Works great.
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Mueller
post Aug 16 2005, 11:42 AM
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the standard MSD box has no logic, all it does is get a signal to fire and it gives juice to a coil, for crankfire (wasted spark I'm guessing you want), the MSD will not be able to switch back and forth, you'll also need a device to control spark advance....for a pure race only motor, you could just setup max advance and it'll work if you ran two MSD boxes

the cheapest method I've seen is using the ignition from a pontic sunbird, no tuning, you are stuck with the factory advance curve, but it works (Clay did it years ago), next would be EDIS or find another 4 cylinder car that you can salvage parts from.

if you want to spend real money, Electromotive is the next step...
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Sparky
post Aug 16 2005, 11:47 AM
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QUOTE (Mueller @ Aug 16 2005, 09:42 AM)
if you want to spend real money, Electromotive is the next step...

I knew if anyone would chime in it would be the MasterMueller!! I'm a cheap bastard so Electromotive XDI is out of the question, unless I hit the lottery.

Got anymore details on the Sunbird setup? I've been looking at the way some of the rotary guys have been setting them up but they stil use the dizzy.

Thanks!
Mike D.
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lapuwali
post Aug 16 2005, 11:56 AM
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QUOTE (Mueller @ Aug 16 2005, 09:42 AM)
the standard MSD box has no logic, all it does is get a signal to fire and it gives juice to a coil, for crankfire (wasted spark I'm guessing you want), the MSD will not be able to switch back and forth, you'll also need a device to control spark advance....for a pure race only motor, you could just setup max advance and it'll work if you ran two MSD boxes

the cheapest method I've seen is using the ignition from a pontic sunbird, no tuning, you are stuck with the factory advance curve, but it works (Clay did it years ago), next would be EDIS or find another 4 cylinder car that you can salvage parts from.

if you want to spend real money, Electromotive is the next step...

Some MSD boxes appear to have an input for a Hall-effect sensor, but I don't know much about what it does. I expect they only work with HEI distributors (trigger wheel advanced by the distributor) or the like. They do have some crankfire setups, but like Mike said, I think they're also basically fixed advance, which is fine for drag cars and the like.

For actual ignition control with crankfire, you'd need to use either the Electromotive HPV setup (very expensive, like $800+), which uses a 60-2 toothed wheel you'd have to mount somehow (probably behind the fan). You can use a DIY system called MegaJoltLiteJr, which uses a small bit of electronics to hook up a Ford EDIS system. Much cheaper, at roughly $200, and fully programmable, but you still need to mount a toothed wheel (36-1, this time), and ther's a solder it together yourself aspect. Other than that, you're looking at just using the ignition side of an aftermarket fuel/ignition ECU. SDS and Perfect Power will both handle magnets on the rim of the fan, but you're looking at roughly $1K to get there, more or less.
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Verruckt
post Aug 16 2005, 12:23 PM
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QUOTE (Mueller @ Aug 16 2005, 11:42 AM)


if you want to spend real money..

Didn't you start a thread a while back, about building a budget crankfire?
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