Staged injectors with MS ?
Turbo Mini Forums

Just a quickie - does the MS allow the use of 'staged' injectors - where a second identical injector is bought in at a fixed RPM point and the fuel count halved - ideally with a trim command to make the switchover seamless?

This would certainly get round the issue of the injector(s) being so large that they flood the engine at idle and only just fuel it at full hit.
It's the route I plan to take in my testing...

yes it does

AlexF

The MSII does not but it has the possibility of using 2 maps, one per injector driver. This is more trouble for tuning but it allows more flexibility since you can have different size injectors and decide how they are staged as a function of rpm and load.

By the way, my initial code has that feature.

regards,
Jean

http://www.jbperf.com/

Another point: if you want to have an idea of what is available in MSII you can download Megatune and run it even without having the ECU. Just go through the menus and you'll see the options and what it would be like to tune with it. You can use the standard MSII ini file or use the one I posted on the MS forum.

Regards,
Jean

http://www.jbperf.com/

Why not use V3 then?

Alex

AlexF

V3 instead of?
V3 refers to the PCB layout revision. I think pretty much anything you can do on the V3 can be done on the earlier revisions, they just require more jumper wires and use of the prototype area, instead of all of the components having their own sockets or such...
MS2 is the processor. The original MS was an older, low power processor so the firmware was written in ASM. MS2 gives more flash memory, RAM, processor speed and precision. It allows the use of a higher level language© to write the code to make it easier to follow.
On a personal note, I disagree w/ their philosophy of the new C-based firmware code which was to make it as much like the asm as possible. As cool and as powerful as asm is, it is difficult and ugly to work with. If higher level constructs are available(as they are in the C language), they should be used where appropriate to make everyones life easier, and the software will become more useful.

-Tyler
DO NOT TOUCH MY HORNS OF DOOM!

I have added staged injection to my initial code. This is similar to the MSnS-extra code staging except that it's only triggered by RPM but you still can get 2 injectors of different size. The staging is activated when the highest RPM point is reached and disabled when the RPMs come down to the lowest RPM point. In addition to that, the second bank of injectors is no longer used for cranking and prime pulse when in dual table or staged injection modes. That way if you have 2 injectors per port, only the primary one is used when starting the engine.

I also added the possibility of having 2 different sets of injector characteristics. So you can have different injector opening time and PWM parameter values. That means that you can mix low-Z and high-Z injectors on the same port, so you can for example have a small high-Z primary injector with and very large low-Z secondary injector. That should help get a good idle with a very highly boosted engine.

I will post the code in the same thread as before on the MS forum.

It would really be useful if we could have a place where we can put those files. There is a sourceforge project for Megasquirt but I'm not familiar with the procedure for using this.

Regards,
Jean

http://www.jbperf.com/

AlexF

That then as I understand it must be the most advanced ECU out there! This is amazing stuff. I'm downloading the code into Megatune now to have a play. Then I have to decide on the best hardware approach, going on the turbo 850 which will make 160 bhp tops, (998 bore, 850 crank, 936cc).

Peter

Editor

MAGA7INE
Seven Magazine
The brand new quality Classic Mini Tech and Journal
Issue 1 out late 2027.

nah any std ford ECU outstrips it... even rover mems does!

One fueling map with a couple of corrections is simple stuff in the modern world. Ford's ECC V has about 650 maps it cross references! :o

Alex

AlexF

I just meant aftermarket ones really, though sounds a bit more complex than you have stated TBH. Maybe I am just thick :)

Peter

Editor

MAGA7INE
Seven Magazine
The brand new quality Classic Mini Tech and Journal
Issue 1 out late 2027.

There are even extremely complex aftermarket ECU's. They just happen to be very expensive. They also tend to include alot of features that I personally will never use.
Personally all I am really looking for is a simple inexpensive programmable fuel and ignition control system. If I could program a distributor and carb with a few buttons, and they both had a feedback loop, I'd go with those. But having to re-jet(or needle) carbs and respring dizzies makes the tuning process incredibly slow and therefore inaccurate.
I'm not saying it can't be done, just that 99% of the time, it WON'T be done.

-Tyler
DO NOT TOUCH MY HORNS OF DOOM!

Yeah pectel T10 is expensive LOL

Alex

AlexF