Megasquirt MS3 & MS3X
Turbo Mini Forums

Did we decide that it was possible to common up two injector drivers to a single injector?

We now have the second MS3/3X unit, so we can do some alternative strategy testing over the winter, once we have an MOT on the 998Ti.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I think we decided that it was the way Rover did it with MEMS (to be able to use a "standard" 4 channel MEMS driving two injectors) as that is what the MPI wiring diagram clearly shows, and that if the MS3X uses normal FETs or MOSFETs to drive the injectors, the same should apply.

There is only one way to find out :)

Personally I have future-proofed myself by adding an "OR" chip at CPU logic level in case I ever want to try MS3 but that's mainly because I need individual P&H output drives for my low z injectors.

Schrödinger's cat - so which one am I ???

This is them:

http://www.datasheetcatalog.org/datasheet/...ics/mXtwyzy.pdf

As you say, best give it a try :)

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Looking at the datasheet I don't think it will be a problem having them paralleled but hopefully Jean will see this post and confirm one way or the other.

Schrödinger's cat - so which one am I ???

I don't see an issue with doing that.

Jean

http://www.jbperf.com/

Well, I can look forward to a bit of closed loopiness :)

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I should add that I'm curious to see what you want to do. Is it simply the dual pulse mode? The difference with MS2/Extra is that you'll have to use the same timing for inner and outer cylinders. But you can play with trim so you should be able to get the correct fueling.

Jean

http://www.jbperf.com/

Exactomundo :)

Dual pulse, closed loop on inners/outers.

Potential idle pulse width issues, but I've found some 1200cc injectors for secondaries, so primaries can be 600cc which I should get away with.

Thanks BTW.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Sorry for dragging up an old post, but I'm just trying to understand the difference between the MS2 and MS3 injector timing.

Am I correct in saying that the MS2 single pulse mode is before TDC intake?

And is the MS3 then before or after TDC compression?

So a value of 145 deg in MS2 would be 145deg before intake on 1 thus fueling both 2 and 1.

It would make sense if the MS3 was before TDC compression if the 360 and 145 are then added together - this is where I am confused!

You are correct.

I had to add 360 degrees to the injection timing table from the MS2.

That's before I had to take it all off again when I put the cam sensor 180 degrees out :(

Just highlight the whole table and hit the plus sugn, enter 360, press OK and job done.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Thanks for that it's appreciated, I'm slowly starting to understand the basics!

I've been reading some of the manual as I was not sure how the VE table worked in terms of calculating the fuel to be delivered (now understand the basics).

I'm now wondering how you have set up the engine and sequential settings as there are only 2 (primary) injectors.

Have you set the number of injectors to 2 or 4 here, if it is 2 does the MS then just output to injectors A and C? Or is it 4 and you are just using outputs A and C and B and D are not connected.

Is the req fuel set as per fully sequential - i.e would the injector size be set to 460cc/min (for each of a pair of MPI primary injectors) or does this have to be doubled up if there is one pulse feeding 2 cylinders?

The ECU is setup for 4 cylinder sequential, with staged secondaries.

I've just connected up A & C to the primaries and E & G to the secondaries.

You need to use the required fuel based on twice the engine capacity.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Thanks for that.

So the MS really thinks it is running a 4 cyl in fully sequential mode, but only using outputs A and C (for primaries). Single pulse then doubled in size as you stated.

Correct.

It is very easy to setup in that way. I fitted the MS3 after warming the engine up on the MS2. It was still warm when I got it started on the MS3. After an hour or so on the road, I had near perfect fuel distrubution at WOT.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Yes, you could. You would have to use the cylinder trim feature.

However, there may be pulse width and staging issues that I still have to get my head around.

I never got around to doing the testing as the 998Ti failed its MOT and is now being broken up :(

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

cool as paul im really thinking that id like to have a go at doing a staged injection turbo mini with the 1098 like what you have done with the 998 3 injectors per port i have been looking at the MS3X ecu but i think i have lot to learn about it are there any places i can look at the programing like how to kind of things and what parts are completable like injectors sensors and coils id like to do a cop set up i live making stuff and i have decant welding skills so manifolds wont be to much trouble unless i do a alu inlet might get that welded by a pro donno for now i need to sort out what id like to do and how im gona do it..

There is quite a bit of info on here about most of the items you said if you have a search. I think the MS is set up to run with GM sensors, but you can run others if you have a calibration curve. I found the MS manual and forum really helpful to understand how it all works and it also gives details on how to connect it up.

Have you read our build guide?

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=329735

It's mainly MS2 based but a lot applies to the MS3.

Also recommend Dave Walkers book for an overview of EFi.

Edited by Paul S on 30th May, 2012.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Wrong thread, that was just the contents page for comments

Try this

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=408438

Schrödinger's cat - so which one am I ???

New MS3 Pro. All the good points of the MS3 & 3X but with better tach circuits and waterproof case and connectors.

http://www.youtube.com/watch?v=SYec40tugsQ&feature=youtu.be

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Looking at the Pro it has a very limited market imo just because of cost, cost would be more than an Emerald or MBE

They should just design a case with ampseal for the ms1/2 or 3-3x for the DIYer this would appeal much more imo

http://www.jbperf.com/