Driving more injectors with Microsquirt?

[MontyR]

Recently I completed a Microsquirt installation on my 84 CJ7 with a Renix 4.0. Still working out the tuning bugs, but so far pretty pleased with things.

My next project is a BMW M73 V12. I really like the form factor of the Microsquirt with the AMPSEAL connector. I also like the fact that it is factory assembled. It has a nice set of features and the price is right. It also has dual ignition output which is very useful for the V12 because it has two VR sensors 60 degrees apart. I plan to use Ford EDIS6 modules to supply spark to each bank of cylinders. The Microsquirt would be perfect for this application, except that it only will power 4 injectors per channel.

Could I power 6 high Z injectors per channel with a small series resistor on each to keep the total amperage below 5 amps? It would only take about a 4 ohm resistor per injector to make the numbers work.

If that won't work, are there any expansion boards or is there a replacement driver that I could solder on the board that would handle 6 injectors per bank?

Monty

[24c]

Hi Monty

I realise you like the Ampseal connector and I assume the v3 MicroSquirt, but have you looked at the MicroSquirt Module and putting that in a case. I only ask as you can add a couple more injector channels, but going back to your original idea, why not just get a couple of injector driver boards, like this guy makes.

They've always worked for me (ignition), but obviously you'll need to case them up, and only end up with 2 x 4 channels.

However, read this thread, and Al aka grippo has a good suggestion part the way down.
Plus try searching for "V12" using the Search... box.

Mike
PS This might be relevant too.

[MontyR]

Mike,

Thanks for the info!

I have been trying to use search, but for some reason it lets me search about 1.5 times, and then it says "sorry you can't use search right now"

Does anybody else have this problem? It is very frustrating. Right about the time I feel I am getting close to answers it shuts me down and won't let me search any more

[24c]

Monty

Yes the Search... box plays up, but just give it a pause, and hit refresh and it'll be OK. I used to think it was a demand thing, but I just think it's being "grumpy".

Mike

[Matt Cramer]

Recently I completed a Microsquirt installation on my 84 CJ7 with a Renix 4.0. Still working out the tuning bugs, but so far pretty pleased with things.

My next project is a BMW M73 V12. I really like the form factor of the Microsquirt with the AMPSEAL connector. I also like the fact that it is factory assembled.

It's a bit of a higher price point, but the MS3-Pro also uses AMPSEALs and can run 12 injectors fully sequential. It's kind of intended to be the MicroSquirt's big brother.

It has a nice set of features and the price is right. It also has dual ignition output which is very useful for the V12 because it has two VR sensors 60 degrees apart. I plan to use Ford EDIS6 modules to supply spark to each bank of cylinders. The Microsquirt would be perfect for this application, except that it only will power 4 injectors per channel.

EDIS would require a 36-1 crank trigger, and there also needs to be a delay for the SAW signal to the second EDIS module. Current code does not support this.