Microsquirt 6 cylinder waste spark batch fuel?

[andrew_mx83]

I would like to use a microsquirt v3 on my I6 engine. I have setup another of these engines using MS with 3 ignition outputs and 3 injector outputs as waste spark / batch fuel in the past.

I've found evidence of people using WLED or ALED on the microsquirt as additional ignitor outputs, is it possible to use one as an injector output as well?

Thanks in advance, id really like to use the microsquirt on a couple of upcoming I6 projects, after installing one on a Mini recently I was quite impressed with it. I much preferred the smaller size/ampseal connector to the usual ms3x combo.

[racingmini_mtl]

You can only have 2 injector outputs. But you can still drive 3 injectors per output in batch mode. And you can have 3 ignition outputs for wasted spark. Check the manual for the Microsquirt in the link at the top of the page.

Jean

[andrew_mx83]

Thanks for the reply Jean. I'll have to have a look into whether 2 injector channels will be sufficient for my application. N/A, 12.4:1CR and reasonably big cams, pump fuel.
The stock ecu has them wired like you've suggested in 2 lots of 3 injectors.

[Paul_VR6]

I have run micro on more than a few vr6 engines (they're setup just like inline). Three spark outputs and two fuel channels. Setup the two banks 123 and 456 that will run smoothest.

[andrew_mx83]

Awesome!!! Great to hear somebody has done it on a 6
Do you notice much difference in power, smoothness or driveability between that setup and full or semi-sequential?

[rickb794]

If you are not boosting the crap out of it and have huge injectors I don't think you will notice much/any difference between batch and sequential.

Size your injectors conservatively so they are not oversized.

Another issue you may have is Siamesed intake ports found on some I6's, as I understand it they are very tricky to get right, if at all.

[JelmerS38]

I run Micro on my V6. Runs perfect. Like Paul VR6 says, run 123 and 456 on each injector output.

[andrew_mx83]

Thanks for the input guys. Looks like a good way to go.

[Paul_VR6]

There is a small difference in idle smoothness and accel can be tuned a little better with sequential. Power is the same, even did dyno testing to verify.

[Tassuperkart]

I have a project to do which is a Z1300 Kawasaki straight 6 bike.
These engines run perfectly down low on a single injector driver pulling in all six injec tors together so i see no real necessity to need more than the 2 injector outputs.

[andrew_mx83]

Thanks for the replies guys. Looks like batch will be ok but I'd still like to get semi sequential if I can.
After a bit more of a look at the product family I've decided that the diypnp is a better fit for me (need to make it look like a stock ecu).
Since it's based on the microsquirt I'll ask here... the documentation states you cannot run stepper motor idle and sequential injection together. So what about semi seq?
WLED becomes spark C
ALED runs an intake VSV
Stepper driver uses PT6, PT7 and PB4

Still leaves me with PA0 and IAC (fidle?) pins spare. Can I use one of these for the 3rd injector driver, or as one of the stepper outputs?

Planning to buy the Nippon 52 pin kit which has the stepper chip on the adapter board and also order the sequential module (if I can use it)

[racingmini_mtl]

PT6 and PT7 are the only outputs for the additional injector drivers (that's a CPU output constraint). So you cannot use them for the stepper chip. The code allows you to use the 2 spare ADC outputs and FIdle for it but I have no idea if that's possible with the kit you mention. You will need to ask your kit vendor.

Jean

[andrew_mx83]

Thanks for clearing that up Jean.
So I would use PT6 for injector channel 3.
Leaving me PA0, IAC (fidle), PT7 and PB4 free to run the stepper chip and one left over. How do I select which pins are used for the stepper chip in tuner studio? I had a quick look but couldn't see anywhere to set what programmable io pin does what.

[racingmini_mtl]

Look under idle control in the Startup/Idle menu. And you can't just use any pin combination but the ones specified there. You need at a minimum spareadc and fidle.

Jean

[andrew_mx83]

OK got the list of options up after loading the correct firmware into TS

So spareadc and spareadc2 can be used as outputs as well? I thought they were just inputs (oops)

All 3 stepper options except using PT6 and PT7 require a spareadc pin so looks like I'll have to give up realtime baro, knock or stepper idle to run the 3rd injector. Might just stick with batch fire...

Thanks again for the help Jean, you're an asset to the community!

[rickb794]

You could use a 2 wire PWM idle speed controller like off a Ford? (or Bosch 3 wire?)

[andrew_mx83]

You could use a 2 wire PWM idle speed controller like off a Ford? (or Bosch 3 wire?)

This does seem like the most logical solution, even though I just rebuilt my stepper IAC valve. I ordered the ecu last night, along with the sequential module. Will have to get a Ford pwm unit and see where I can easily install it.

Thanks to all for your input

[rickb794]

You can mount the Ford valve on a block of aluminum drilled and tapped for hose fittings like the DIY has done with their stepper adapter.

https://www.diyautotune.com/product/cus ... iac-valve/

[andrew_mx83]

OK guys I've finally got the engine running on the diypnp in waste spark with direct coil control and semi seq fuel

I haven't got the stepper motor idle working yet. I wired the stepper driver on the adaptor board to fidle (iac pin) and spareadc as above which must be the step and direction inputs for the driver. I'm guessing the third pin which TS doesn't use in this configuration is the enable pin for the driver. Should this be tied to ground, 12v or 5v rather than just left disconnected? Surely the driver isn't getting an enable signal currently?

[andrew_mx83]

Datasheet for the stepper driver attached.

I guess the easier question is, what does the cpu output to pin PB4 normally? This is tied to 4 pins on the driver, I01, I02, I11 and I12