GM ECM vs MS in E30?

[ForcedFirebird]

Anybody tried it?

I'm using a modified (hacked) $58 code GM ECM (Syclone/Typhoon Turbo, speed density ECM, 3BAR MAP support) in my twin turbo Firebird and was wondering if anybody has looked into it VS the MegaSquirt swap.

I've owned 2 MS units and ditched it in favor of learning the GM code for various reasons, the knock sesnsor circuitry is reliable, they are cheap to buy, tune and mod. The modified $58 code (labled $59) has a lot of the nice features that MS does including autotune, anti-lag, speed-sensitive boost control, among a whole list.

It is a little more difficlut to grasp, any thoughts/comments?

Cheers, John

[moatilliatta]

subscribed, sounds interesting.

[Rolla1990]

Never heard of it... Sounds very interesting...

[ForcedFirebird]

As far as I can tell, we use the same injector style and impedence as GM. Off to a good start :D

What kind of ignition control does the BMW require? What kind of voltage etc for timing control? It will be easier not to have to make/adapt some kind of ignition.

[SamE30e]

Links.. Sounds good.

[bender]

i think this would be cool to look into.. might have to switch over the trigger wheel?

here is some info i found

http://www.diy-efi.org/gmecm/ecm_info/1227749/

[SamE30e]

Moreeee info!

[Six_Shooter]

:woowoo:

Dizzy, is it magnetic trigger, optical, or other?

[nando]

:woowoo:

Dizzy, is it magnetic trigger, optical, or other?

other - VR sensor. the dizzy is electrically controlled, there are no moving parts inside other than the rotor.

if you were going to use a GM ecu, I would use EDIS coils and trigger wheel, ditching the stock cap & rotor altogether. The only thing is GM's firing order is different - V6 vs I6 - but I think you can get around that just by swapping plug wires to the right coils.

how much tuning support is there for this? the nice thing about MS (and other popular ECUs) is the vast amount of support, information and software available to tune them. I just have to wonder if there is a reason this has never caught on if it was so cheap and easy to work with.

[ForcedFirebird]

other - VR sensor. the dizzy is electrically controlled, there are no moving parts inside other than the rotor.

if you were going to use a GM ecu, I would use EDIS coils and trigger wheel, ditching the stock cap & rotor altogether. The only thing is GM's firing order is different - V6 vs I6 - but I think you can get around that just by swapping plug wires to the right coils.

how much tuning support is there for this? the nice thing about MS (and other popular ECUs) is the vast amount of support, information and software available to tune them. I just have to wonder if there is a reason this has never caught on if it was so cheap and easy to work with.

I was just discussing that idea with Six_Shooter last night. It just so happens, I have a custom external DIS wheel, ICM, and coils just need a few sensors. May even nab them from the junk yard, just so happens I need something anyways (hopefully Ill see a 1227730 ECM :D)


EDIT: Check out thirdgen.org 's ecm sections or code59.org plenty of support.

[Six_Shooter]

other - VR sensor. the dizzy is electrically controlled, there are no moving parts inside other than the rotor.

Cool, then to retain the dizzy, an magnetic conversion would likely be needed. I've thought about ways to trigger an ICM (GM) with a non magnetic trigger, but haven't prototyped it yet.

if you were going to use a GM ecu, I would use EDIS coils and trigger wheel, ditching the stock cap & rotor altogether. The only thing is GM's firing order is different - V6 vs I6 - but I think you can get around that just by swapping plug wires to the right coils.

I'm already working on that, there's a couple small issues that will need to be worked out, from what I've found so far. The GM DIS is just about as easy to adapt as the Ford EDIS, the only difference is the EDIS has aftermarket reluctor wheels available from places like DIYAutotune.com, or use an Escort wheel found at a wreckers, where as the GM reluctor wheel is less easily obtained. There is only one source currently that I'm aware of for the reluctor wheels and are meant to be used in FWD swaps when using the 3500 non-VVT, swapped into older chassis' that use the older coil packs. I have a reluctor wheel that my grandfather and I made 6 years ago for use in a frankenstien V6 swap, the block didn't have a CPS location, so I went external with it.
Anyway, the only reason I'm looking at and wanting to get the EDIS to work is because the V8 EDIS is much easier to find and retrofit than the GM 8 cylinder DIS (N*). The Ford EDIS only requires the 36-1 wheel, regardless of cylinder count. The GM 4 and 6 cyl DIS uses a 7x "low res" reluctor wheel (could be refered to as a 6+1), the 8 cyl DIS uses a 52x "high res" reluctor wheel, and there so far undetermined if the cam position sensor is used by the 8 cyl DIS module, or not. I have to think it does, since the cam position sensor connects to the DIS, then is fed through to the ECM.
So the Ford EDIS for the 8 cyl applications looks to be the nicest plan of attack.
For the 4 and 6 cyl applications, it would likely be easier to just use the GM DIS.

how much tuning support is there for this? the nice thing about MS (and other popular ECUs) is the vast amount of support, information and software available to tune them. I just have to wonder if there is a reason this has never caught on if it was so cheap and easy to work with.

There is more support than people are led onto believe. As FF said, look at TGO in the DIY PROM forum, lots of information there, $59 has it's own site at www.code59.org, plus many, many other websites.

I think people are overwhelmed with all the tables and constants and scalers that are available in the GM binary, most you will never need to touch, but they are available. I also think that people are thinking that you need to hack the binary your self, when most of the most common programs are already hacked, and have plenty of documentation about them.
There's also software and hardware support sites, like www.tunerpro.net and www.moates.net, that have many items for the GM ECM and other ECMs as well.

John, just take the ECM out of your 'Burd, you won't need it in there any time soon. :p

[ForcedFirebird]

John, just take the ECM out of your 'Burd, you won't need it in there any time soon. :p

Already planned on it :P

Either way, I'm visiting the yard and will see if I can hunt one down.


I'm also planning on making a connector to hook the e30 ECM back up easily as a "just in case".

I might stop and buy a manual for the 30 and scope out the wiring diagrams and see what wires need to be swapped (unless someone here can PM/email one to me, hint).

Fuel and spark is all I'm going to do (piggyback) more than likely.

Also already have the 3BAR MAP, but will need the other GM sensors, and maybe throttle body from GM. Not sure if it will be easier to fabricate a IAC or TB adapter, probably the latter.

The whole reason behind this is since the timing belt is overdue, I want to see if I can grab an i head since the car will already be dug into, and this will give me not only the oportunity to tune for the mod, but leave open the option of boost later.

Although, Chris knows my thoughts on high compression/low boost, I want to keep the 30 more rliable than the motor I'm building for the Firebird

[ForcedFirebird]

Actually picked up an ECM for the project.

Does anybody know what kind of signal the stock 'puter sees for the electronic speedometer? ie whats drives it etc?

[DaveSmed]

Squarewave, via magnetic reed switch contacts in the diff pulling to ground.

Not sure about pulses per mile though.

[ForcedFirebird]

Thanks Dave.

Looks like I might be following in Six_Shooter's footsteps and using a cluster form a GM and a BMW to make a "hybrid" speedometer with the optical speed sensor. Probably easier than reverse-engineering the bimmer's system.

Next on the list is to nab a harness for the under-hood ECM (I have one that can be hacked, but is incomplete), then find/fabricate locations for the rest of the GM sensors.

The knock sensor should be fun to find a spot for :P