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Microsquirt
https://slantsix.org/forum/viewtopic.php?f=26&t=64253
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Author:  Reed [ Mon Nov 25, 2019 7:59 pm ]
Post subject:  Microsquirt

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?

Author:  MadScientistMatt [ Tue Nov 26, 2019 5:18 am ]
Post subject:  Re: Microsquirt

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

Author:  Greg Ondayko [ Tue Nov 26, 2019 8:19 am ]
Post subject:  Re: Microsquirt

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

Author:  Reed [ Tue Nov 26, 2019 9:05 am ]
Post subject:  Re: Microsquirt

16 x 16 fuel and spark tables

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

Author:  Dart270 [ Tue Nov 26, 2019 1:31 pm ]
Post subject:  Re: Microsquirt

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

Author:  Reed [ Tue Nov 26, 2019 3:19 pm ]
Post subject:  Re: Microsquirt

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.

Author:  emsvitil [ Tue Nov 26, 2019 4:15 pm ]
Post subject:  Re: Microsquirt

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

Author:  DadTruck [ Tue Nov 26, 2019 5:08 pm ]
Post subject:  Re: Microsquirt

Quote:
microsquirt will trigger off of an HEI ignition system.



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/

Author:  Greg Ondayko [ Wed Nov 27, 2019 4:29 am ]
Post subject:  Re: Microsquirt

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

Author:  DadTruck [ Wed Nov 27, 2019 6:14 am ]
Post subject:  Re: Microsquirt

Quote:
locked to trigger the MSD Box which now sends signal to Your microsquirt / megasquirt


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.

Author:  Joshie225 [ Wed Nov 27, 2019 7:26 am ]
Post subject:  Re: Microsquirt

DadTruck wrote:
Quote:
microsquirt will trigger off of an HEI ignition system.


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.


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?

Author:  Greg Ondayko [ Wed Nov 27, 2019 8:21 am ]
Post subject:  Re: Microsquirt

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

Author:  Joshie225 [ Wed Nov 27, 2019 12:12 pm ]
Post subject:  Re: Microsquirt

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.

Author:  Greg Ondayko [ Wed Nov 27, 2019 1:27 pm ]
Post subject:  Re: Microsquirt

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


Thanks,

Greg

Author:  Rick Covalt [ Wed Nov 27, 2019 4:10 pm ]
Post subject:  Re: Microsquirt

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

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