Factory ECU chipping effort...

[hackish]

I thought I'd spend a few hours looking at the possibility of chipping the factory Legacy Turbo ECU. I took one apart and it's got a plug for what looks like a factory upgrade module. Mine had a module installed so I took it apart. Fairly easy to do. Has anyone else looked to see if they had a chip installed on their ECU? This thing is going to get in the way of plugging my ROM emulator in

I'm desoldering the EPROM right now and I'll read the map off it.

-Michael

[hackish]

Just a quick update. I snapped a few photos. I also read the data from the chip. There are a lot of what looks like fuel and ignition tables in the first part of the ROM. I will have to dig up my disassembler and start playing with it. I'm also going to pull the original chip so I can compare. I assume the one I just did is a "factory upgrade"

-Michael

[vrg3]

Michael, after you've done some more poking around, send me a PM and we can compare notes. I don't want to tell you too much of my interpretation until you've already done some of your own -- that way we can see if we have the same interpretations or not.

You'll find that all the data stuff is in the first 8 kilobytes, and the rest is all the code.

Are you saying you had some kind of module installed in the 30-pin very wide inverse socket thingie? Woah. As far as I knew, they never actually made any ROM upgrades for our ECUs. The socket was just there "just in case." I think they actually did end up using these sockets on certain SVX models as part of a recall or something. I'm very curious about the differences between the two ROMs.

After you desolder the 27C256, you could just solder in a socket and then stack socket on top of socket until your emulator fits in, right?

What disassembler are you planning on using? DASMx is what I was using.

[hackish]

Ok, I just removed the original PROM. The location of the tables is a little more confirmed. I have a hunch that the second prom is a limp mode sort. Reason being, most of the map data is quite a bit different.

Until I find my CD for the disassembler and actually disassemble the code I won't know for sure but I think I can see where the fuel maps are and the ignition maps are.

Does anyone feel like doing some R&D? Take your ECU and unplug the expansion card. See how it drives. I suspect you will find it runs rich with a lower rev limiter.

-Michael

[hackish]

You'll find that all the data stuff is in the first 8 kilobytes, and the rest is all the code.

This is exactly what I found. They were kind enough to pad the data as well. Just looking at the hex (something I've done with many many ECUs) I can see where each table row starts and ends

Are you saying you had some kind of module installed in the 30-pin very wide inverse socket thingie? Woah. As far as I knew, they never actually made any ROM upgrades for our ECUs. The socket was just there "just in case." I think they actually did end up using these sockets on certain SVX models as part of a recall or something. I'm very curious about the differences between the two ROMs.

HRM! This is very interesting! I thought that everyone would have a module. I took some pics. It is a brand name hitachi module and doesn't look like anything aftermarket. I suspect this would make for a very simple way to upgrade ECUs.

After you desolder the 27C256, you could just solder in a socket and then stack socket on top of socket until your emulator fits in, right?

What disassembler are you planning on using? DASMx is what I was using.

Since I didn't know that most ECUs didn't have an expansion module I assumed it would have to stay. I'll remove the blue socket and put in one of the ZIF sockets I use for the Honda ECUs I do. I was going to look at the traces to see if they hijack the ^CE pin...

-Michael

[vrg3]

Yeah, that little daughterboard socket is kind of cool. The upper 28 pins map directly to the pins of the 27C256. The ROM-swapping is indeed accomplished by hijacking the chip enable. One of the "extra" pins of the 30-pin socket is connected to the CE pin. The stock ROM's CE has a pull-down resistor (it's active low), so you can just pull it up to Vcc directly on the daughterboard, and tie the daughterboard ROM's CE to ground.

[hackish]

Ok. That confirms how I suspected they did it. The most interesting thing here is how different the added chip is. The comparison between the two should show some interesting things.

The add-on board has
MECF-M51
H93VDS2

The original has:
MECF-M50
H93VDL2

My car has a manual ECU but it was an automatic car so I'm not sure what year or market it's really from. The part number on the ECU is: 22611 AA691

Don't know if that will provide any insight.

I'm going to pull the blue socket and solder in a ZIF. I'll try to get some pics up tonight.

-Michael

[hackish]

ECU with the addon board unplugged.


Closeup of the addon board before I removed the ROM.


I used a cheap shitty socket for this because a ZIF wouldn't fit in. I usually bitch about competitors using these sockets when they chip honda ECUs... Unfortunately I didn't look at the clearance and the black socket interferes with the blue one Just tells me if I get into chipping these bad boys I'll just have to make a few custom boards to plug them in.


Here is the legacy turbo ECU up beside an STi V2 ECU. The plugs are the same. This V2 ECU has already been chipped.


main board with the blue plug removed and a ZIF soldered in.


Done and ready to be installed in my non-starting car!

I guess this should clear any stored codes I'm going to try it first with the original chip from the mainboard. I doubt it will make a difference.

-Michael

[vrg3]

That's interesting to see the daughterboard. Do you know anything about the history of your car or its ECU?

Automatic and manuals didn't have different ECUs. 22611AA691 is an early 1991 ECU. Turbo ECUs had part numbers from 22611AA690 through 22611A694. -0 through -3 were used in 91. -3 and -4 were used in 92. -4 was used in 93 and 94. They all have the same pinouts and are functionally interchangeable.

The STi ECU, as you can see, is completely different inside. It's built by JECS and is based on a Fujitsu M3779something processor. It has a 27C1028 EPROM installed (that's the chip covered in black that makes it an "STi" ECU).

This type of Hitachi ECU appears to be unique to 90-91 North American 5-speed non-turbo Legacies and 91-94 North American Legacy turbos as far as I can tell.

[hackish]

You are correct about the JECS ECU however the chip in black was added after the fact. I can dig around and see if I have an unaltered STi 2 ECU still sitting around. This particular one was a ZeroSports socketted and chipped ECU. Unfortunately there is no market for enhancements on said ECU so I never did anything with it. It was just interesting to point out that the plug was the same.

As for my car, I know the 2 last owners. It has a Starion FMIC, Full 2.5" exhaust. 4.44 short ratio box, special edition slipping clutch, autometer gauges. Upgraded brakes, stainless lines, Impreza suspension (going to swap on my DMS 50's soon as I run them up to Lachute for a rebuild.

Since the turbo is blowing oil I think I may just slap on my VF24 from the STi engine and run it at the factory 12 PSI. The engine has 275k on it and a leakdown showed it to be losing a lot. Not sure if it's carboned up or not. I may re-sleeve the block with some pistons and rods to switch it over to twin cam with my STi heads. At that price though I may just go with a 2.5l short block.

Wait, this is supposed to be a daily driver! I have a Mazda 323GTX with a GT-R engine (350bhp) that needs lots of attention.

One final and interesting note about this car. The injectors are pink. I haven't worked on legacy turbos before but they look like upgraded STi injectors... Oh yeah, it seems to run super rich all the time and 444Turbo was lucky to get 250km from a tank. I suggested it was probably just a bad O2 sensor...

-Michael

[vrg3]

Hmm, it was my understanding that STi ECUs were standard WRX ECUs with chips added. I guess I was mistaken though.

Yes, they kept the same plugs up through 96 or so at least. The pinouts are more or less the same too.

Nothing in that history would make me think someone would have chipped the ECU. Maybe the 22611AA691 units had the same guts as the 22611AA690 ones, but with a chip.

Stock Legacy Turbo injectors are pink; these are most likely the stock injectors. Are they mounted in the rail with the connectors going off at 45-degree angles? That's how the stock ones are set up.

Our stock engine management does run pretty rich on load.

[azn2nr]

judging by the other mods done to the car there may be a chance that the chip may be a vos chip made by adrian vos on the rs liberity board.

how do the pinouts on the v2 match up to the ones on the stock ecu. and have you tried pluging the v2 in and seeing if it would work.

when you said gtr motor for the 323 what exactly is that. i was under the impression that gtr was a nissan designation.

[hackish]

This "module" is a factory hitachi module. It shows no signs of being altered in any way and still has factory labels over the window. I highly doubt it is in any way aftermarket.

The 323GT-R was a very rare homologation special. Then Mazda dropped their rally program. Car runs 12's but is rusted to pieces. I'm sure this legacy would be happy to make low 14's so it would be nice to make it hit 13's before the end of the summer. The more projects start piling up the more I think I should just wire it up with a PSITech and be done with it.

-Michael

[stipro]

A tidbit of info somewhat unrelated to the original topic.

when you said gtr motor for the 323 what exactly is that. i was under the impression that gtr was a nissan designation.

The GTR motor was the motor for the japanese market, and is mainly used for motor sport. Essenctially, it is over engineered to make more power. There is a 323 GTR Rally car in Canada that turns out 419hp @ 7800 rpm + 356 ft-lb @ 6000 rpm with 30psi of boost.

Now back to your regularily scheduled topic!!

[azn2nr]

hackish, do you have any info on this psitech ecu. and is there any way you can wire it into the legacy plugs and correct pinouts so that its plug and play.

also as i asked above. how does the v2 pinouts look compared to the legacy ones.

[hackish]

when you said gtr motor for the 323 what exactly is that. i was under the impression that gtr was a nissan designation.

The GTR motor was the motor for the japanese market, and is mainly used for motor sport. Essenctially, it is over engineered to make more power. There is a 323 GTR Rally car in Canada that turns out 419hp @ 7800 rpm + 356 ft-lb @ 6000 rpm with 30psi of boost.
[/quote]

That was Bert's car. Not sure who he bought it from but it was built by the Ericksons. I bought one of his spare engines sans turbo.

I tore a GT-X and GT-R engine down side by side. There are lots of stories about magical innards but the short of it is they have better rods, trick (hollow cast pistons with a cooling channel), and sodium filled valves. The turbo was one of the best and most rare parts. Big roadblock in making more power... I've been porting these cylinder heads and building these engines for a little while now. Very well built engines.

-Michael

[hackish]

hackish, do you have any info on this psitech ecu. and is there any way you can wire it into the legacy plugs and correct pinouts so that its plug and play.

also as i asked above. how does the v2 pinouts look compared to the legacy ones.

The PSITech ECU. We will be doing a plug and play for late models. It's doubtful that I will find time to write throttle code this year but maybe next year I will have a plug and play for the STi.

I haven't decided yet on how to price or feature it out. It's got a lot of features that you just don't get with the common units.

8 injector drivers (others can do things like control fans etc)
8 coil drivers (same deal with the extras)
2 wideband controllers on the board.
2 EGT controllers onboard
2 knock channels on board with DSP and support for per-cylinder knock detection.... yes folks it can tell you which cylinder is knocking
2 VR or hall effect triggers. In the case of the Subaru it would be configured for 2 VR sensors, cam and crank.
VFD display drivers (this is an option)
PS/2 keyboard support.
Full PID based boost control
Antilag
blah blah blah.

Once I'm happy with the packages I'll write the manuals and do up the marketing stuff.

-Michael

[azn2nr]

so its gonna have widebands and knock sensors built in and you are gonna do a plug and play model for the legacy???


if so, freakin sweet. all i have to say is hurry up.

oh and another thing. how about an auto tune feature?

[hackish]

If I could get a few committed orders then yes, I will do a plug and play. First I must get my own running. I don't like to ship an ECU without at least a base map so the car and be started and maybe driven around the block.

As for auto-tune the firmware supports it. It's a feature I prefer to implement in the tuning software. The reason for this is that I'm never willing to stake an engine on a $100 O2 sensor.

In the future I'll probably add a long term fuel trim feature or something like that. Something I like about this is the VFD display can be made to fit in most dashes where you'd find the clock.

The system would also have to be "more or less" plug and play since it would definitely require the user to feed in the plug for the wideband. The ECU also has some 30A coil drivers to run GM coils. I'd have to either deal with driving the subaru ignitor to drive the subaru coils or bypassing the ignitor and just driving the coil pack directly.

Does the legacy have a PWM or stepper driven idle controller? I know my 2.5RS had stepper driven, my STi v4 had PWM, the STi V3 and V2 I did for people had PWM...

-Michael
-Michael

[NICO]

first of all hackish where are you located in canada? second of all i own a 323 gtx and a legacy turbo i think we have the same intrest here. my gtx is not bad its got about 260hp out of the 1.6l and is in mint condition, no one in north america has one in better shape then mine its got orig paint and no rust i mean no rust for a canadian car and only 200ks on it. my legacy is my other baby soon to be a impreza L sedan 800lbs less will get me going very fast.

about your work on this ecu chipping there is a guy in toronto that did my chipping for me, about the pic of the ecus u got up with the blue socket, he siad it could not be chipped for some reason. so he had to use my factory ecu out of my 91 legacy turbo it only had one chip thats it no blue thing.

if your close to hamilton and need some parts i got 4 legacy turbo ecus, if your going to make a engine manigment for this ecu and need help i will help you out cuz this is all i need done to make my car a misssle.

ps please let me no cuz this is pissing me off that i cant get a engine mangment system for this car

[azn2nr]

depending on price and time frame of avaiblity vs the legacu and the price and avaiblity vs teh plug and play pm standalone i will be looking in very closely to this.

[vrg3]

The VOSChip isn't compatible with Hitachi ECUs.

The v2 ECU pinouts are the same as the Legacy Turbo's aside from the 4-channel vs. 2-channel ignition. So you can't just run a Legacy Turbo on the STi v2 ECU without other changes.

[hackish]

STi V2 has a 2 channel ignition. Has the same ignitor as a legacy turbo. It uses COP but in the chassis harness they are connected in pairs to the ignitor.

-Michael

[hackish]

first of all hackish where are you located in canada? second of all i own a 323 gtx and a legacy turbo i think we have the same intrest here. my gtx is not bad its got about 260hp out of the 1.6l and is in mint condition, no one in north america has one in better shape then mine its got orig paint and no rust i mean no rust for a canadian car and only 200ks on it. my legacy is my other baby soon to be a impreza L sedan 800lbs less will get me going very fast.

Imagine the chances! I think I've seen you on the GTX mailing list. Small world. My GTX is a pack of rust with a big turbo. Right now the engine is out of it. It's a BPC8 with a hybrid TD06 20G turbo. FMIC, 720cc injectors, GM coils etc. Soon as my legacy is running properly I'll start working on it.

about your work on this ecu chipping there is a guy in toronto that did my chipping for me, about the pic of the ecus u got up with the blue socket, he siad it could not be chipped for some reason. so he had to use my factory ecu out of my 91 legacy turbo it only had one chip thats it no blue thing.

Well I think maybe he just didn't look hard enough. Probably a legacy ECU and a legacy turbo ECU are very similar. I'm not sure if the legacy turbo uses a boost solenoid or if it's just run off the wastegate. If so then the lack of a solenoid driver may be the only difference. Honda ECUs are very much like this. I can take a DX ECU and add vtec drivers, add a knock board etc and it becomes a GS-R ecu.

[QUOTE.if your close to hamilton and need some parts i got 4 legacy turbo ecus, if your going to make a engine manigment for this ecu and need help i will help you out cuz this is all i need done to make my car a misssle. [/quote]

As with anything it just takes time and money. I'm short on both these days I am in the capitol region but I do occasionally travel to Toronto. I'd like to get the car running before making any commitment.

-Michael

[vrg3]

Oh, wait, I forgot you said that already.

Then the STi ECU ought to be able to run your EJ22T. It won't run right, since the MAF sensor is wrong, but it should run. So maybe you could try seeing if your engine starts with the STi computer.

I actually was able to start my car using a WRX ECU with 4-channel ignition. It didn't run well, but it idled on two cylinders.