I have read that the microsquirt will trigger off of an HEI ignition system. Can anyone confirm this? Is it triggering off the 7 pin HEI module or the four pin?

Yes.

A 4 pin HEI would have the MicroSquirt controlling just fuel, triggered off the coil, like this:

http://www.msextra.com/doc/pdf/html/Mic ... .4-76.html

A 7 pin HEI paired with a locked distributor (like a Lean Burn - that's what I'm using) would let the MicroSquirt control timing. There's a wiring diagram for these modules here:

http://www.msextra.com/doc/pdf/html/Mic ... .4-85.html

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Matt Cramer
1966 Dodge Dart turbo / EFI project

What is the total Cell Map availability for Micro squirt?

8X8?
12X16?

I was just thinking about a microsquirt vs msIII for a next installation.

Greg

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http://www.youtube.com/hyperpack

16 x 16 fuel and spark tables

https://www.diyautotune.com/product/mic ... -ecu-only/

Yeah, this has got me thinking too. I don't want to put a crank trigger on my new supercharger motor (pulley/space), so maybe microsquirt is the way to go.

Lou

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Home of Slant6-powered fun machines since 1988

I have been thinking of the cleanest, cheapest, and easiest EFI installation and I keep coming up with microsquirt. I am thinking HEI triggering the Microsquirt with two batch-fired injector banks (or maybe TBI) and wasted spark. A 16x16 spark/fuel table shouldn't be too much tuning to deal with. Self-learning would be nice, but you get what you pay for.

I have enough hardware to do two SEFI MAF systems based on Ford components, but I have three vehicles I am thinking about injecting.

I believe there's 2 different operating systems (firmware) that run on the microsquirts from two different companies.


Make sure you pick the one that does what you want

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

used a seven pin HEI with a locked Lean Burn distributor

When I ran the 68 Barracuda at the strip, I would get intermittent spark plug mis fires at high load and high RPM,, I am sure the engine I was running did not have the best piston ring sealing and I am sure that my fuel tune was not the best.
I swapped the ignition over to a MSD box,, with no changes to the engine or the fuel tune and the mis fires went 100% away. Still using the Lean Burn distributor.

Not saying that the HEI is not a good ignition, but on my car the MSD gave vastly superior results.

I buy my MS stuff through DIYAutotune, I have got great support from them.
There is also an online support forum

http://www.msextra.com/forum-info/

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Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

So John in your situation you use the Lean burn locked to trigger the MSD Box which now sends signal to Your microsquirt / megasquirt etc...?


Greg

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http://www.youtube.com/hyperpack

actually the two wires on the lean burn distributor both go to the MegaSquirt ECU, there is a wire that connects the
ECU to the MSD box that triggers the MSD to fire. The wiring is really simple.

To allow the spark to happen at the exact correct moment, there is a 'timing wizzard' within the MS set up process that
assists one to set the actual locked ignition timing within a specific window. Once that is done, working from that known setting the MS ECU
adjusts the firing of the ignition to occur (fire the MSD box per your desired timing curve) as you have inputted.
That is my 'garage mechanic' interpretation of what happens.

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Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

There are many bad replacement HEI modules floating around. A friend had a bad Chinese 4-pin that gave a misfire problem. I gave him a used GM module which fixed the problem. LT1 Chevy guys are struggling too. Do you recall what brand you used?

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Joshua

I too have had bad 4 pin gm modules on non efi cars..

I went back to chrysler electronic ign box from hei conversion as I was getting tons of misfires and it broke down with the family and had to get towed.

What are the good hei 4 pin modules?

MSD or others?

Thanks for clairifing john.. that makes sense.

Timing input control to mS and then its map controls msd which fires your coil.

Greg

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http://www.youtube.com/hyperpack

I've been fortunate enough to find good used GM modules in self-serve wrecking yards when I've needed them. The MSD replacement was supposed to be a good one in years past. The reviews at Summit Racing are mixed with 12(!) one-star ratings. I'd probably skip it as it's an expensive part at $110 even if it does have rev limiting. The Davis Unified Ignition module has good reviews, all 4 or 5 stars and costs $49.50.

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Joshua

At this point I would definently trust the d.u.i. piece over msd.


Thanks,

Greg

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http://www.youtube.com/hyperpack

AC/Delco ones are on Rock Auto for $20 couple bucks?

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6