GM Stand Alone ECM Swap

[WDRacing]

Just wondering, but how much better is this then the MSII? I'm just a big fan of real time tuning and you simply can't beat the price.

WD

[Chezedik]

Does MS2 offer real time tuning? If so, not much, in fact it is about the same price. There would be no advantage to one over the other, except that the GM should offer a true Sequential Multiport injection system, I would think.

[WDRacing]

That is true, however, I'm staying with the MSII until alot more people are running this GM unit. MS already has a huge following and great support.

WD

[Edub1]

Here is a link about doing this swap into a Ford. Discusses distributor issues.

http://eelink.net/~p-nowak/EEC....html

These ECUs can be bought for next to nothing and have just as much control - and can be tuned by your local GM tuning pro.

Like I said, if we can get one done professionally for 460cc injectors, we can pass it along and simply change a few key values. DIY is great but I'm done ****ing around and not getting to enjoy my car. Actually my tune is alright - I think my IACV is cloged.

Anyway, this swap would be better.

[WDRacing]

Better then what?

[Edub1]

Better then what?

Better than a half baked tune done on an ECU with 99% of it's functionality unknown. I don't know of anybody who has been able to make a great tune on the E motor. There is that damn tip in problem and I'm still working on getting the car to idle right without stalling while coming to a red light.

In fairness, I think I might have an IACV or TPS issue but I'm just getting frustrated and I'm wondering what is going on without my knowledge that might be slowly destroying my motor. Like maybe subtle, transient detonations caused by some glitch somewhere that nobody knows about but will take their toll over time.

The way I see it, the fully decoded GM ECU is practically a stand alone unit for practically nothing. It uses MAP and is designed for turbo apps, has full control over everything, like injector correction based on voltage fluctuation, fan operation, etc. It even has electronic WG control.

Open the XDF file with Tuner Pro and just look through some of the functions.

[Chezedik]

Actually, I believe that the WG control requires a separate module.

[pr240sx]

Its easier and cheaper to get some Supercharged stuff out a any GM car.the Syclone, Typhoon, Turbo Buicks and Turbo Trans Ams all share the same sensors and pickups as the supercharged guys.Now, after 92, programming became a little harder thanks to OBD regulations.Now the cheapo ECU are Turbo Buicks. Most of these guys are removing their ECUS in favor of the FAST or Haltechs. Also, keep in mind that you can use TurboLink to reprogram or get Pitbull ECU chips (for 80 bucks or so USED) on the web.Sensors are easily found, and yes, there is a wastegate ELECTRONIC actuator harness. But usually fails when running more then 15 psi of boost (as per GN stock boost)

[Edub1]

Ah, see now that's the kind of input we need - thank you.

I wonder if some type of dash mounted control could be fit to the electronic WG. Clearly, one could run a Hobbs switch or two and some toggles and have their choice of boost levels. I'd be happy as hell with two.

pr240sx, do you know how closely our sensors match the GM ones? I'm guessing most sensors operate withing reasonably similar voltage ranges. Is this assumption more or less true?

Also, I think the local guy told me there is a small distributor mod that needs to be performed. I'm going to swing buy there and bug him a bit more.

[Bernard]

http://home.swbell.net/loeryder/prom.html

Have fun with your project. I would like to see where this goes.

[Chezedik]

Most sensors operate on a 5v signal. Unfortunately, they will have different voltages at different ranges. If you can come up with a table, this is pretty easy to calculate and program for. The real hard part as I have said, and probably the hardest part of all will be the IAC, since as I have pointed out, they operate on two different methods. One is PWM and the other is a stepper. But you said you have a guy who can make an adapter, and I think that I would just put that into the IACV line, jam the AAC all the way open, and unplug it.

[Edub1]

I don't know much about those systems - in fact I'm dealing with a AAC problem right now, damn idle surges from normal to 1500 and back, over and over. I cleaned that and the IACV to no avail.

Anyway, what is the difference between the two systems in terms of function? From having mine off today it might even make sense to make a flange that fits a hose and remote mount the GM unit some where. Both devices essentially do the same thing, no? Then, why block off the AAC? What's the reasoning there?

[Chezedik]

You would open the AAC all the way, and then on the hose, create a special T fitting, where one was in, an out, and a seat that would let the IAC screw in and then block airflow as necessary. This would allow the IAC to control airflow using the GM system.

Otherwise, you would have to make a custom manifold and use the GM MAF.

Neither is a bad option.

[Edub1]

Without getting to far off track,

It would be super easy to convert the AAC into a plate with a hose barb for that matter. The question is, once this is done and the GM sensor mated up, would the issue be resolved or would there be further considerations?

I'm only concerned with function, the fabrication should be cake.

I'm guessing the GM sensor would jive with the GM ECU and do what needs to be done.

[Chezedik]

That's it. Everything else is just a matter of changing tables or changing sensors. And of course wiring it in or routing the factory harness.

[Edub1]

I don't know if my current problems are tuning of part related but I'm about at my witts end with this ad hock tuning.

[Chezedik]

Word.

[Edub1]

Well, turns out my ECU was bad and I was able to get the new EC3 code running so I'm not as down on the ECCS tuning as I was, but anyway... Here is an email I sent to Craig Moates and his reply.

Hi, myself and a number of other guys are trying to put together an ECU swapfor our Nissan 240sx. The ECU we are looking at is the GM 1227749 from theTurbo Sunbird & 91-93 Typhoon/Syclone - with the 3 bar upgrade of course. Iam told that I will need a 4.3L turbo memcal to use with these ECUs. Is thisa type of chip, do you sell these or an adapter? I have your Flash & Burn -how does this system work and what else will I need to get these going?

Any info you can give us would be greatly appreciated.

Thanks, Eric

Hi Eric,

That is a great ECU. I'm not sure about the memcals. Check with Terry athttp://www.rosesandwrenches.com and he should be able to help you out. He doescustom harnesses, and has a ton of ECU parts, sensors, etc. Tell him I sentyou.

Best regards,Craig Moates

[Bernard]

Well, turns out my ECU was bad and I was able to get the new EC3 code running so I'm not as down on the ECCS tuning as I was, but anyway... Here is an email I sent to Craig Moates and his reply.

Hi, myself and a number of other guys are trying to put together an ECU swapfor our Nissan 240sx. The ECU we are looking at is the GM 1227749 from theTurbo Sunbird & 91-93 Typhoon/Syclone - with the 3 bar upgrade of course. Iam told that I will need a 4.3L turbo memcal to use with these ECUs. Is thisa type of chip, do you sell these or an adapter? I have your Flash & Burn -how does this system work and what else will I need to get these going?

Any info you can give us would be greatly appreciated.

Thanks, Eric

Hi Eric,

That is a great ECU. I'm not sure about the memcals. Check with Terry athttp://www.rosesandwrenches.com and he should be able to help you out. He doescustom harnesses, and has a ton of ECU parts, sensors, etc. Tell him I sentyou.

Best regards,Craig Moates

What was wrong with your ecu? And what has changed?

You will want the sunbird ecu/memcal if you want to use the gm dist signal for the ecu. You will want the Grand Am ecu/memcal is you want coilpacks and the gm cas signal. You cannot use a 6cyl cal on a 4 cyl. How much less is this system than a megasquirt?

[Edub1]

The ECU is way cheap. Don't know about the other parts. I like the Megasquirt option but who tunes it and how advanced is it? This would be a matter of giving the car to a pro and having him make one perfect tune - and then reproducing the tune with minor mods.

I understand there is now this colum ECU for the DE that is sweet - it tunes in real time. I'm thinking, I can get this EC3 code working right for now and might go DE for my next motor.

This GM system is worth investigating though. Electric WG = hell yes.

[Chezedik]

Are you talking about Calum's new Biki alternative. I liked his daughterboard, and his service was excellent, so I will consider that too.

[turbodig]

Funny you guys should be talking about this now, we're just getting started with a project to extend the functionality of the code used in the Syclone/Typhoon/Sunbird '749.

But, as discussed in the thread so far, we do know pretty much all the table locations/values/flags, and have TunerPro definition files defining it all.We're also working through a bunch of the documentation of the existing functions. This will all be a freeware project, with the stiputation that all tunes you come up with based on this code, get posted back to the code project.(Kind of a sourceforge for ECMs)

The site is http://www.code59.org. We're currently in an invite-only mode while we get some of the kinks worked out of the web site and stuff, but I suspect we'll soon be fully public.

Regarding your existing sensors, you may be able to re-use some, depending on the format. Basic crank sensor waveforms also tend to work.

This ECM has been used on everything from Mustangs to Porsches to 1st Gen Camaros, and I don't see why it wouldn't work for the import crowd as well.

Later,

Dig

'91 GMC Syclone - 11.83@112 | Stock, with 20g.

[Edub1]

Welcome to NICO turbodig.

I sure hope you will keep us updated on the project. In the mean while, I'm going to look into making it fit. I hope others will be doing the same. can you think of anything you know we will need off the top of your head? I know we will need a map sensor and a memcal but I'm not familiar with memcals - would you elaborate on this for us? Also, what kind of air meter does this system use?

As for tune sharing, I'm down with that...as long as nobody gives any info to any Honda owners.

[Chezedik]

Why would Honda want to use this anyway, PG-MFI RAWKS!

In most cases when using a MAP, you don't use a MAF, and I would guess this is no different.

[turbodig]

Honda guys are too busy with CHROME...

Basics to make it run:

MAP sensor.TPS (0-5v)o2 (dang near anything works)crank/dissy pickup Speed sensor (square wave, expects 4000 ppm but there are ways to convert)Coolant temp sensor

I don't know much about your ignition/timing mechanism.... the ECM does control timing, but I'm not sure how it would relate to what you have. The Motec web site has a lot of good docs on timing waveforms.

Also, you'd either need the GM idle air control, or try to make yours work.

It will do knock control as well, with a GM sensor.

Our updated code reads a WB o2 sensor, as well.

There are a few outputs you can use if you like - Wastegate control, EGR, A/C, cooling fan control. Don't have to use them to make it work, but they're there.

MEMCALS - in general, find a memcal from an app that's similar to your engine displacement and config. 4cyl, 6cyl,8cyl. The knock detection filter portion of the memcal works better if your engine is a closer match to the one it was designed for.

DIY-efi.org is a good place to ask about hybrid questions. syty.org has a few guys that have hybrid apps, but mostly GM vehicles. thirdgen.org has a lot of cross-platform guys as well.

later,

Dig

[Chezedik]

Yep, that's exactly what I expected.

[Edub1]

Damn near everything on that list is a check. I don't know much about distributors or how speed sensors work - perhaps someone who understands them a little better will chime in. The FSM is here http://www.nicoclub.com/FSM/240sx/1989-90/ and it has info on the dizzy - E theory IIRC.

Anyway, TPS should mate up and the idle air control can simply be fabed up. Also, I'd think the Turbo Sunbird would be the closest memcal. Are these in the ECU?

Modified by Edub1 at 6:59 PM 4/5/2007
Modified by Edub1 at 7:00 PM 4/5/2007

[Edub1]

Quote from sil80drifter.

Ok, so on the SOHC (and DOHC) there are two types of valves (three actually two are combined into one).1) I.A.A Valve - (I.A.A - Idle Air Adjustment Valve) which on it has A.A.C Valve and an F.I.C.D valve. this is the square thing, on the very back of the manifold which has two components:

a)The A.A.C Valve is the Auxiliary Air Control valve, which according to the FSM is "actuated by the ECU by an On/Off pules, and the longer the On pulse, the more air it lets through.This to me is the real idle valve, on the side of the I.A.A assembly, it's the round cylindrical thing with a connector. (brown connector in pic)

b)The FICD valve (the long 6 sided thing sticking out in the back of the I.A.A assembly) on the other hand according to the FSM "Compensates for changes in idle speed cause by the operation of the air compressor (wtf, either A/C or the air pump for eissions) And also has a vacuum control valve installed to prevent an abnormal rise in intake manifold pressure during deceleration." (purple connector in pic)

Then, a completely separate unit is there called the Air Regulator. It is on the side of the intake manifold, a cone shaped sort of thing, which connects witht a thick hose to the I.A.A assemblyThis is the valve that provides anair by-pass during cold idle. It doesn't have a solenoid, and isn't controlled by the ECU, it simply has power and ground, and inside a bimetal element which opens the bypass at low temps and closes it at higher temps. (on the very left in pic, gray connector)

NOW. I am probably going to keep the Air Regulator, because it's very simple, and only needs a [+] and a ground.

The real question is: What to do with the I.A.A? Remove it completely, block off the rear of the manifold, and control idle with the throttle plate?

Leave it there and somehow attempt to control the A.A.C. with the standalone (Megasquirt in this case)? I def won't need the FICD, so I'm not going to connect that one at all, no matter what.

Who has a standalone and has controlled their idle with the throttle plate?

Should I try to figure out how to control the AAC with the Megasquirt? I didn't see much literature on their site to understand how it can be done....

_______________________________________________________

Also, are we sure the AAC solenoid isn't a stepper? What's the difference and what is the difference in signal?

[Chezedik]

Yes, if you look at the data in Consult it clearly shows it is duty cycle (as was indicate by sil80's quote as well). The stepper GM uses is pulsed. One pulse = 31' of rotation, and this is 1 step. As it screws in or out, it may be 31 steps or whatever. But it is not duty cycle controlled, like ours are.

EDIT: I will tell you about the signals when I get out of class.

[Brandon93240]

There's a guy who comes on here sometimes, Halnfl, he works at a shop down the street from mine, that guy knows ALOT about GM"S, he use to work at House of Speed with Mr. Kent(world famous twin turbo TNT Viper guy here in Houston). He does alot of tunes on GM's with his scan tool(matco with SPS). I'll try and get ahold of him and see if he wants to do something about this. I remember his Grand National he use to bring to Rankin Rd, that this was a beast.