Jump to content
LegacyGT.com

5EAT TCU Reverse Engineering


utc_pyro

Recommended Posts

  • Replies 614
  • Created
  • Last Reply

Top Posters In This Topic

We could purchase the CD for $75...

 

Or...

 

You can just download it from there: http://ken-gilbert.com/wrx/mans/Subaru_J2534.zip :cool:

 

We would still need the actual Subaru data files that are located on the CD, that link is just a flashing interface / program if I'm not mistaken.

Edit - finally got it to download (169mb file), you were right & good find! I can't seem to open the flashwrite / PAK File List of N.America for SSM-3.mdb file or I would try to dump some of the info to an excel file (still not sure if TCU data is included or not).

Edited by rubberman
Link to comment
Share on other sites

Sorry, but I don't exactly follow here. What is the overall goal of running this program? Is this the tool we use to re-flash the TCU after someone has broken the code (kernel) to change the programming.

Not that I can add any value to this. I am interested in possibly electronically changing the TCU for my 5EAT (along with a ClimberD HEX F? / Transgo / whatever mechanical mod for 08+).

Link to comment
Share on other sites

The Hex F1 is a mechanical set of modifications. This would be changing the software programming to get a similar or even better result. Both ways are very complicated to figure out, and this TCU hacking is much harder in comparison. It is also the best possible way to solve the problem of crap shifting. But it also requires the hackers to know how a trans works, and it took me many months of attention to really understand how shift logic is programmed. It's not as easy as hacking a single table and changing certain cell values. This thing will be as complicated as the ECU, though not all of it needs to be reverse-engineered. That said, this would be the best possible way to do it, as the software as is does some finicky things that are a pain to work around. Edited by ClimberD@HexMods
[CENTER][B][I] Front Limited Slip Racing Differentials for the 5EAT now available for $1895 shipped, please inquire for details! [/I][/B][/CENTER]
Link to comment
Share on other sites

Right, I totally understand your Hex F1 is solely a mechanical change. You state that a software mod could do similar or better. In my mind (and that's a deep dark place that even I avoid) the ultimate would be a combination of the two. Mechanical mods to improve line pressures, spring changes, opening up (drilling), etc and any beefing up that can be done given typical available parts (not including custom parts). The electrical/software mods to improve transmission strategy for things such as the crappy shift timing, RPM points, etc.

I agree that the programmer (he better be a damn good software engineer) must also be a transmission expert and quite possibly a electrical/hardware engineer of some type. IMO, if the ECU can be cracked, so can the TCU. It's going to take someone above me to do it! Our problem stems from demand. All it takes is enough demand from a group for a company to invest in the R&D to do it. That or a talented and dedicated DIY'er from one or more of the occupations above.

Link to comment
Share on other sites

TCUs with Nissan and GM are hacked, so you are correct it's simply a function of talent and time.

 

I don't know what the stock line pressure duty cycle is, but if you hacked it and zero'd out the shift solenoid ramp up / ramp down, and max'd line pressure by zero'ing that solenoid, my total guess is that it would hit hard enough without any mechanical modification. Frank_ster has the opposite opinion, that it's probably not enough to do just TCU. He knows more than I do. He recently went the Hex F1 direction instead of installing the MegaShift transmission controller board. I do not know much more than that. I thoroughly understand the shift control logic of both the PCS and MegaShift control units (PCS being much more sophisticated but also much more expensive and lacking an output for displaying what gear you're in). Subaru / Jatco would probably add even more bells and whistles, but that's all they would be. Anyways, It would be great if the TCU was hacked. But someone would have to do it...

[CENTER][B][I] Front Limited Slip Racing Differentials for the 5EAT now available for $1895 shipped, please inquire for details! [/I][/B][/CENTER]
Link to comment
Share on other sites

if anyone else has noticed, new version of romraider can connect to the 07+ TCU's with canbus. However, there are only a few parameters you can log, much of which the ecu already logs (thr plate, rpm, gear)....so....this is progress..... before this we (07+) couldn't use SSM to connect to the TCU at all
Link to comment
Share on other sites

i will go to the mega shift in conjunction with the hex mod valve body.

hoping for faster shift response times, want slightly lower shiftpoints for the buick engine.

and hoping to have the torque lockup sooner in city driving for better economy.

see if 2nd gear lock up is possible.

 

it seams to be that subaru engineers designed the 5 eat to have attributes of a cvt. they got the feeling down but the thing is the torque converter is slipping soo much to do so. instead of keeping the turbine speed up shift later to produce less heat. liek the 4 eat does ..

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

i will go to the mega shift in conjunction with the hex mod valve body.

hoping for faster shift response times, want slightly lower shiftpoints for the buick engine.

and hoping to have the torque lockup sooner in city driving for better economy.

see if 2nd gear lock up is possible.

 

it seams to be that subaru engineers designed the 5 eat to have attributes of a cvt. they got the feeling down but the thing is the torque converter is slipping soo much to do so. instead of keeping the turbine speed up shift later to produce less heat. liek the 4 eat does ..

 

2nd gear lockup is not only possible, the 350Z does it in sport mode. Nothing to stop you!

[CENTER][B][I] Front Limited Slip Racing Differentials for the 5EAT now available for $1895 shipped, please inquire for details! [/I][/B][/CENTER]
Link to comment
Share on other sites

^ yes but it may be hydraulically unavailable in first and second in the 5 eat

gm's in not available in 1st gear . part of limp home so you can actually drive off with out stalling your car in case the sol is jammed on.

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

In my 2008, I can get lock up in 2nd gear. If I put it into manual mode, rev up to 4-5k, it will stay there off throttle, not like in 1st gear where the revs will fall off throttle no matter what.

 

TCU mods would kick ass, especially for the newer cars.

Link to comment
Share on other sites

if SSM can read/flash the TCU, then we can. I'm thinking about hounding the ppl over at romraider to investigate the possibilities....

 

Stop thinking about it and lets do it. We really need a solution to the 5EAT owners wanting better than stock performance.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



×
×
  • Create New...

Important Information

Terms of Use