Ideas for 4 cylinder MPFI = Toyota 22RE with GM ECM?

[EagleMark]

$88 is ~100%, A1 is ~100%, DF is ~100%

Woo Hoo! All can be run manual? All can be run SD?

Tech support included?

[RobertISaar]

natively speed-density. native manual support.

tech support... i wouldn't call it native, but i do know where a few of the pitfalls of them are. for instance, except for DF, none look for a clutch switch signal for any reason. they do attempt to determine if the clutch is being depressed though, via a few scalars. it wouldn't be difficult to add in a patch to any of them if necessary to use a hardware clutch switch. i did for nAst1 as an option.

[Six_Shooter]

Why has no one suggest nAst1 yet?

[RobertISaar]

the constant state of development(or lately, the constant feeling of "urgh" when i think about having to rewrite sections of code(some mine, some GM), so i avoid it until i feel less bad about it)?

[EagleMark]

It's a pretty simple engine, cam, small bore and some head work but that was for kicks. It's a rock crawler and the low RPM stable is more important. Don't need anything fancy, just did'nt want to start with a major re work of XDF/dissasembly...

With all the help I got here this looks like a simple conversion for the Toyota MPFI already on the engine, new truck is carb. So this will work well!

Will be checking injectors that are in it and see what they are? So many parts have been changed I have no idea but will re read info given by 1project2many gave. He seems to know a difference in early late MPFI intakes and injectors.

[JeepsAndGuns]

Can someone give me some more info on this nAst1. I have seen it mentioned in several threads, and from what I gather, its a custom code mask written by Robert? Just curious.

[RobertISaar]

Can someone give me some more info on this nAst1. I have seen it mentioned in several threads, and from what I gather, its a custom code mask written by Robert? Just curious.

A1 (as if nAst1 didn't give that away), modified to include monsterous 400-8400RPM VE and main spark tables, support for using either of tables in speed-density or alhpa-n, a new idle VE scheme(done in full alpha-n, not a hybrid, with IAC compensation), skipshift kickdown for the 4T60E, TCC PWM for 4T60E, brainless auto mode for the trans(shift every time the shifter moves, whether up or down) trans temp tracking/action, 3 step rev limiter(in both fuel or spark cut varieties), above 1BAR MAP support(up to 3BAR allowed, 2D spark and fueling correction for now), IAT/IRT correction to spark, 4 circuit PRNDL decode, added clutch anticipate/correction stuff, MAP above which PE always enabled, full closed loop idle fueling allowed, along with various fixes to factory code when necessary.

that's all for the moment, progress has stalled(no pun intended) for now due to not being able to fit anything else into a 32KB BIN, so i have to design a MEMCAL adapter to allow as much of the 64KB space to be open for the progam as possible, since the way GM designed the PCB, only 32KB BINs are normally possible.

[1project2many]

I was out of town for a few days so I missed out on this. I've been doing four cylinder ecm stuff for a few years... maybe longer than most. I can answer quite a few questions about differences in configuration for many of the common and a few less common four cylinder engines.

Mark, it really seems like you're trying to wade across a river in plain sight of a bridge. My truck mostly fits the bill for what you're doing and I would expect it would make a decent model for another GM ecm swap. However, if you're looking to roll your own I can offer some guidance.

GM's 7 notch DIS was first released on the 2.3 Q4. Q4 DIS module and ignition coils mount underneath an aluminum cover on the top of the engine. There are no plug wires. The coils are housed in a special, hard plastic box which also contains conductors to route spark to the plugs. These systems are really designed to fit this engine. The coil box is not easy to adapt to other engines. It's not uncommon for these systems to have issues with repeated misfires and internal shorts and many people will remove the coil box and connect coils used with the 2.0 / 2.2 / 2.8 / 3.1 / Northstar engine instead. I've done it and it works. The stock ignition module is retained. Look around j-body.org for a "2.4 coil relocation."

The 2.5 distributor was replaced with 7 notch DIS when the "4tech" version of the engine was released. That ignition module bolts to the side of the block and attaches directly to the crank sensor. There is no wiring harness between the crank sensor and module which means that a wiring harness might not have a means to clip to the module. I would probably avoid using this module and sensor due to physical mounting and connection troubles.

The Chevrolet Cavalier 2.0 was first equipped with 6 notch DIS in '87. This is the most flexible system I've seen yet. It uses dual terminal coils with proper ends for plug wires. The coils attach to the module to keep the total system footprint small. The module attaches to an aluminum plate on the side of the engine block which can be removed and adapted to other locations. The same module was carried forward to 1993 in cars and possibly 1995 in S10 trucks once the 2.5 was discarded in favor of the 2.2. The Corsica / Beretta family also used a 2.2 for a short time. This module is an electrical replacement for a 7 pin type HEI distributor and should work with any GM ecm that uses REF, EST, and the 5V bypass wiring scheme. In 1994 the Cavalier ignition system and ecm were modified so the crank signal was fed to the ecm directly, and the ecm triggered the each coil independently. The module looks the same but it is not interchangeable with earlier versions. The 2.2 and 2.5 crank sensors are not interchangeable electrically with the 2.3 Q4 sensor.

Two years of Pontiac Sunbird with overhead cam engine came with distributorless ignition. This system is not DIS. It is a system similar to Bosch distributorless ignition systems found on BMW and other European cars which utilizes a "40+1" tooth design. The crank signal is sent directly to the ecm and the ecm triggers each coil independently. This is a somewhat unique design to GM North America and for the most part, the ignition and ecm should be considered "married." As this is a European engine that was only used in this configuration from 92 - 94 in the US, there are no calibration files I'm aware of for tuning this ecm. A similar system is used on Daewoo cars sold in the US (Daewoo is owned by GM) but although those cars use GM OBDII compatible underdash PCM's, again, there is no tuning support that I'm aware of.

After covering ignition systems, there is the choice of pcm. The 4tech 2.5 and the 87-90 2.0 / 2.2 were TBI equipped so unless you want to run four port injectors in TBI mode (it's been done) those ecm's are out. The 2.3 quad4 used a 7749 in it's first year or two but then swapped to the 8707. The code used in the 8707 does not seem to trigger injectors when used in the 7749. The issue may be as simple as adding a 1X signal from the module to the ecm although there is a large question of where to attach that signal at the pcm. There is some additional hardware inside the the 8707 which may detect this 1X signal. Some of the 7749 equipped cars came with a version of code which will work in both ecm's and might be a starting point for a 1 BAR engine. The Q4 tables go to a much higher rpm than most GM engines and even a mild 22R/RE will see but there's nothing wrong with a little overkill. I don't know of any complete disassemblies for that code which has so far prevented using it with another engine.

The Cavalier was the second vehicle I'm aware of which received a flash type ecm. Manual trans equipped 2.2 Cavaliers in 92 and 93 received a very simple box that had limited tuning parameters. The code was programmed onto a ROM and only the tuning parameters could be changed via upload. Auto trans equipped cars had a traditional prom although they were likely simple also. In 94 and 95 all 2.2 cars received a memcal equipped ecm. I *believe* the 95 Cavalier PCM is a P66. It's certainly much different than previous versions. I have a partial disassembly here and you could probably find one with more commenting on j-body.org. No Cavalier prior to '95 uses sequential injection. Power to the injectors comes from a common source in 92-93 and is split across two wires in 94 but the ground sides are separated into bank one and two in all three years.

The S10 trucks also used PFI equipped S10s and we're extremely lucky that Ward Spoonemoore left us a disassembly in the $0D hack. Those trucks were equipped with a 7427 so I'd imagine that's a good ecm to use in truck country. We have calibrations floating around so the only remaining issue is finding a memcal with the correct cylinder select value. It shouldn't be too hard with the info that's turned up in the last couple of years.

Toyota wiring is strange, to say the least. You're actually better off starting with a carby truck as you don't have to integrate much of a Toyota harness with the GM wiring. Good thing! I spent many, many, many hours looking at multiple diagrams to figure out what to do with Yota engineering's efforts.

Since you didn't mention DIS at first I didn't discuss it. I still have the prototype spacer here I used to make the crank trigger wheel. 22RE engines are known to need timing chain and / or chain guide replacements from time to time. When I designed the spacer and wheel I made it so the main balancer retaining bolt could be removed without disassembling the trigger wheel / spacer / lower pulleys. This makes it easier to pull the balancer and timing cover. You're welcome to use the spacer as a model, or I'll take measurements from it. There are a few changes between prototype and actual part such as better self centering of the spacer and trigger wheel and slight adjustments to length. I'll offer to machine a spacer here but it will take some time before I can get to it. If the older engine drives the oil pump off the crank then the distributor can be removed completely. This really cleans up the engine compartment.

Hope this clears up some confusion. I have GM training manuals, service manuals, and wiring diagrams available if you need them during this project.

[EagleMark]

Well the kid and I got a 1228708 ECM and harness from a Quad Four lumina I think? Also picked up a 1227727.

Injectors in the Toyota engine a Low Impedance Peak And hold which seems to be what the Quad Four 8708 ECM is set for. Not sure about the 7727? Or about netres changes for a 4 cylinder? Seems like the easy choice would be 8708

But from re-reading this thread I think we for got to get the Quad Four ICM to run the DIS.

ALso not sure if I got the right four cylinder DIS, it was off a 2005 2.x engine. All the early ones were gone. Wonder if this would work? If not get correct DIS if this one won't work?

Dave W made me drawings for the crank trigger and spacer for the Toyotas balancer and Jesse can cut them out at work. The $8B has a reference angle of 74.88, so I should be able to adjust to get timing correct, if close without having to make an adjustable crank sensor mount?

[EagleMark]

Here's the DIS coil and ICM I got. 97-01 CavaLier

[delcowizzid]

down here we use the 1927A dis module and 7 notch trigger wheel on 4 cylinder conversions
.we have a great number of custom 4 cylinder setups on our forum and drawings of the trigger wheels theres a lot of wheels forsale on ebay nowdays to save making them

[1project2many]

DIS module must be from 87 to 93 Cavalier. 94 and up the coils are directly triggered by the ecm/pcm.

Those ecm's will work with either high or low impedance injectors. Make sure you pull the Toyota resistor box out if using peak and hold driver.

Cavalier DIS requires 60 deg reference angle. Be sure to install wheel at angle that matches DIS system or base timing will not be correct.

Quad 4 module might work but system is physically tougher to adapt. No plug wires, everything is bolted under engine cover. I'd stick with Cavalier system. Might have to do something for 1X signal though. Cav module may have one available that isn't usually used.

[dave w]

The pic below is a Quad 4 external mounted trigger wheel. The mounting holes allow clocking if need be.

dave w

[xtreamvette69]

my best advice would be to keep it simple, the following is a pretty simple, basic old schoole ecm that even has a pretty trouble free starting solution.... best of luck lol

[EagleMark]