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has any one hacked the legacy ecu?
Posted: Fri Mar 14, 2008 6:58 am
by jeffast
i am curious if their are any tools to reprogram the ecu on the legacy turbo. I was talking to a guy with a newer wrx today and he had his laptop plugged into his odb ii port and he was using his stock ecu as a full stand alone. i was wondering if any one had gone this far with the t-leg ecu
Posted: Fri Mar 14, 2008 7:00 am
by DLC
The early Legacy ECU isn't programmable.
The difference between your ECU and the one in the WRX is exponential.
Posted: Fri Mar 14, 2008 7:34 am
by Arctic Assassian
bullshit. Any computer is programmable, you just have to have the right tool. how do you think EM solutions are made, reverse engineering, and reprogramming of existing components before a prototype is made.
Posted: Fri Mar 14, 2008 8:02 am
by 555BCTurbo
Arctic Assassian wrote:bullshit. Any computer is programmable, you just have to have the right tool. how do you think EM solutions are made, reverse engineering, and reprogramming of existing components before a prototype is made.
Then why hasn't someone done it in the 17 years that these cars have been around?
Posted: Fri Mar 14, 2008 8:19 am
by PhyrraM
The BC/ BF turbos use a Eprom. This is what is normally reffered to as 'chipping' the ECU. The EJ20G versions have been reverse engineered. The Ej22Ts have not, that I have ever seen.
The N/A BC/BF probably has an eprom also, but I cannot say for sure.
Posted: Fri Mar 14, 2008 4:35 pm
by Arctic Assassian
No one has done it because look at subaru Official numbers on how many were made. We all know there are more than that out there, but manufacturers never batted an eye at "that tiny little company that made a fast car that made it around a track 100 million times" back in 91.
And furthermore, because the 2.2t was only availible here, in a short run, and america has never been import friendly, I don't think anyone has had the chance to do it.
Posted: Fri Mar 14, 2008 5:24 pm
by DLC
You can not plug in an OBD cable and reprogram the ECU. You can not take out the chip from the ECU and reprogram it. You must get a replacement chip, and EEPROM reader/writer, and after copying, reverse-engineering and modifying the chip, you reflash it.
Old Nissan 240SX/Silvias have this same issue. Owners remove the ECU, send it off, and the tuner unsolders the ecu, installs a socket, then puts back in a new socketed chip.
This is why there are no "chips" for these cars.
Posted: Fri Mar 14, 2008 8:25 pm
by Arctic Assassian
Now I see the miscommunication. I percieve the ECU as everything inside the steel case.
Removing the chip, programming a new one, and installing it to me, is, reprogramming.
Posted: Fri Mar 14, 2008 9:44 pm
by 93forestpearl
I was under the impression that the Legacy SS ECU didn't actually have lookup tables like newer cars. Instead that they calculate the fuel constantly. Anyone know for sure?
Engineuity/RomRaider is cool, and allows people to recalibrate their factory ECU's on the newer cars, especially the 32bit ECUs. It does have limitations though.
Posted: Sat Mar 15, 2008 1:03 am
by Arctic Assassian
enginuity is just a hacked free version of ecutek. Pdx tuning wont touch it, on principle, and neither will I.
Posted: Sat Mar 15, 2008 2:26 am
by James614
What's the probability of running a WRX ECU on an EJ22T, since they are so easy to tune apparently? With the prices I see for standalones, I imagine it'd have to be more economical....
Posted: Sat Mar 15, 2008 4:34 am
by jeffast
DLC wrote:
The difference between your ECU and the one in the WRX is exponential.
well no shit,
ok, so i need to convert to a newer ecu, or go to a standalone if i wanna get crazy with bigger injectors and boost
Posted: Sat Mar 15, 2008 6:21 am
by Aerotech
Stand-alone, like Haltech ($1100-1300) or piggyback like Perfect Power 6 ($400). There simply is no market for chipping our ECUs, unless you want to spring for a custom one-off. It's your wallet; how fast do you want to go?
Running a WRX ECU would involve tracing every wire on the plug, and probably re-routing most of them. Have fun.
Posted: Sat Mar 15, 2008 6:52 am
by jeffast
Aerotech wrote:Stand-alone, like Haltech ($1100-1300) or piggyback like Perfect Power 6 ($400). There simply is no market for chipping our ECUs, unless you want to spring for a custom one-off. It's your wallet; how fast do you want to go?
Running a WRX ECU would involve tracing every wire on the plug, and probably re-routing most of them. Have fun.
hrm, i'll have to start doing some research on engine management.
250hp to the ground with 300 ftlb tq and i will be in dream land, but currently i just want to leave stock wrxs in the dust.
Posted: Sat Mar 15, 2008 5:54 pm
by Arctic Assassian
For those numbers you could get a vf39, some sti 550 injectors, an intercooler, a RRFPR(search), An FCD(search again), and a boost controller. Believe me, your not going too crazy, you just want a street killer.
Posted: Sun Mar 16, 2008 2:32 am
by jeffast
hrm, thanks for the food for thought after reading all that it makes me think that standalone is really the way to go for me.
thank you very much.
i started out with svx's so being able to have this many bolt on, or easily availble power mods is blowing me away, their goes my x-mas funds...

Posted: Sun Mar 16, 2008 7:44 am
by Legwerx
um your legacy is also OBD 1.....
WRX's are OBD 2
And I would work on getting an actual PCV system on the car ie; actually hooked up to the intake, or filters rather than open hoses.
Other than that, up the boost to 14 psi, RRFPR, Intercooler, and a 3" turbo back catless exhaust, with a TD04 should get you to stock WRX ish maybe a little under... maybe with a few other tweaks and you'll be fast enough til you can buy stand alone....
Just my opinion

Posted: Sun Mar 16, 2008 8:11 am
by jeffast
Legwerx wrote:um your legacy is also OBD 1.....
WRX's are OBD 2
And I would work on getting an actual PCV system on the car ie; actually hooked up to the intake, or filters rather than open hoses.
Other than that, up the boost to 14 psi, RRFPR, Intercooler, and a 3" turbo back catless exhaust, with a TD04 should get you to stock WRX ish maybe a little under... maybe with a few other tweaks and you'll be fast enough til you can buy stand alone....
Just my opinion

i did rick, i just havent had a chance to show it off yet.
Posted: Sun Mar 16, 2008 12:21 pm
by Arctic Assassian
jeffast wrote:hrm, thanks for the food for thought after reading all that it makes me think that standalone is really the way to go for me.
thank you very much.
If you feel that spending an unnecessary amount of money on a great yet unnecessary tool, then by all means...
I own three turbo legacys, all of them would knock your socks off.
peace.
-Adam
Posted: Mon Mar 17, 2008 3:59 pm
by 93forestpearl
^How have you been tuning? Changing your fuel is the easy part. Its being able to do serious work with your timing that becomes the issue. Also, depending on one's setup, resolution can become a limiting factor.
One can get a plug-in Link G3 for about $1k. Its a sizable chunk of change, but the beauty of it is that it can accomodate anything you do down the road.
Speed-density? Sure. WRX heads with COP? No prob. E85? Check.
I have no regrets on getting my G2. It can do what ever I want it to. My setup is much more agressive than most people's, so I didn't have a whole lot of options. In the end, how far you want to go dictates what you will need EM wise.
Posted: Mon Mar 17, 2008 5:04 pm
by Arctic Assassian
For the numbers he posted, timing isn't an issue. And if you really wanted to kick it old-school... adjustable cam gears...
See, people don't give enough credit to the ej22t ECU. It does an awesome job at keeping things civil, all you have to do is give it good fuel and make sure you have no check engine lights.
Posted: Mon Mar 17, 2008 6:45 pm
by 93forestpearl
True. My buddy was running a GT3076R with just a Maf Translator Pro and it ran pretty well as long as he had good plugs with the right gap.
I wanted more flexibility so I decided to go with a Link. Its not for everyone or the faint hearted though, unless to want to pay someone gobs on money to tune the whole thing. Knowing that my setup would change drastically over time, something that can accomodate that was necessary. I may end up with STi heads and I'd need to be able to use a Phase II trigger setup.
And yeah, with his goals a standalone might not be cost effective. My goals will forever be changing so it was needed in my case.
Posted: Mon Mar 17, 2008 11:36 pm
by b3lha
I have been messing with the SVX ECU and TCU. I'm pretty sure that it's the same hardware as the Legacy but different firmware. On my website are raw dumps and assembler code from the ECU of my SVX, My Legacy and an early WRX. Downloaded through the OBD1 select monitor interface.
I know where the fuel and timing maps are located in the SVX EPROM. But I'm trying to figure out the rest of the maps before I start messing with them. I even made an Enginuity definition file. I haven't really looked at the Legacy EPROM but I can't imagine it's much different.
I am building an adapter that go in the upgrade socket and allow cheap modern EEPROMs to work in place of the obsolete EPROM that the ECU requires. Then I have to get myself an EPROM programmer in order to burn some modified ROMS.
I'm a computer geek (but not nearly as smart as Vikash) and I don't have a clue how to tune the engine. So I plan to document the ECU in the hope that somebody who understands engines will do some tuning and be willing to share their maps.
http://www.alcyone.org.uk/ssm
Just to clarify, I'm talking about the OBD1 JECS ECUs from the early to mid 1990's. Not OBD2, Denso, Hitachi or any other type. Mainly I'm interested in the SVX. If anybody has any technical insight into these ECUs and TCUs, then please email me.
Posted: Tue Mar 18, 2008 1:03 am
by 93forestpearl
Nice. If you could get that worked out, I'm sure many people would be interested, my buddy included.
Posted: Thu Mar 20, 2008 11:24 pm
by schspeedster
Other than the EEPROM, what other memory would retain data after an overnight battery disconnect?