EJ20G "RobTune" Info

[dscoobydoo]

Rob was working on the conversion of COP.
I will let him post where he is at.

[rob]

Ah yes, the overdue update. As mentioned I am spending my time fiddling with the stock ECU to EJ20G ecu changeover; specifically with regards to my ignition conversion idea. I am on my 3rd prototype and still working out the kinks. The plan is to have a small circuit with 8 wires that once wired in will work with the stock ECU or an EJ20G ECU without the need to change any part of the ignition system. It will have two new wires with ECU pins on the end to simply plug into the ECU connector, two input wires to take the ej22t ignition wires out of the ECU, two output wires to go to the igniter, and power and ground. Once I am happy with how the prototype works, I will look to make up a batch of circuits and make available to those wishing to adapt the EJ20G ECUs. I still think adapting to run my EJ20G ecu tune is the best short term option. The results so far have looked good.

I would like an update from Mike since he has been running my tune for a while now and has the most experience.

My protoypte EJ22T ROM board isn't working as expected, I need more time on the bench with it figure out why. I think it's simply how my crazy wire-wrapped board fits into the ecu socket. My goal is to run the car from a stock rom image from my proto board before Drew reclaims his spare SS

Reversing the code has gone no where. As I mentioned before, this is going to be the bulk of the work. I have played around with it a bit, but will need to go fishing for some expertise on the Hitachi code. I should have a borrowed revtronix board in my hands in the next couple of weeks that will help narrow down the areas of the code that I will need to reverse first.

-Rob

[kbeefy]

Thanks for the update, as long as I have the car I'll be interested in an ECU upgrade/Tune.

[rob]

I do believe I have the 4to2 ignition converter prototype working! I just fired up Drew's SS on a stock EJ20G ecu and all appears good. I need to swap MAFs before I give it a test drive, but so far it looks very positive. I'll update when I have more data.

-Rob

[mike-tracy]

Nicely done!

[rob]

Green MAF in and a quick trip around the neighborhood confims all is well. It is running a stock V5 EJ20G ECU with no noticeable driveability issues. I still need to test at higher RPMs, but did get into boost and it ran great. Next step will be put some good test miles on it, and work on the final PCB design. I will start a new thread when I am close to having a production converter available.

[Florin1]

Great news Rob! Nicely done.

[MikeyMeyagi]

heres a copy of my last update to Rob from a few nights ago.
Hey Rob,
Long time no updates! Ive been running the +4 map all summer, and its been awesome, car runs great and pulls hard. Only little issue ive had is once in a while it will go very lean at crusing speeds wih low throttle input, but once it sees boost it comes right out of it. My o2 sensor may be crapping out, and it only does it once in a while so im not too worried about it.

Last night i FINALLY installed those 20G(they are actually from a 260hp EJ20H i found out) cams over had for 6 months, hopefully that yeilds a power increase as well.

I just got back from a test drive with the +7 installed, i swapped it out with no reset and the only time i see knock is if i get into it at around 3k, and as soon as i hit full boost the light will blink once or twice, but thats it. i turned the boost controller down a hare just to be safe, i had it as high as i could go without hitting fuel cut. Upper rpm's are fine, afr's in the 11's and no knock. Car runs good and drives fine though.

A few weeks ago i lined up with a 07 sti with an intake, a full exhaust and a rom tune, from a roll in 3rd we were dead even till i went into 6th, where i pulled a little on him. this was with the +4 and n/a cams. he didnt know how much power he was making, but usually a stock sti will put down 245whp or so and i know he was above that, either way, i was pretty impressed.

I plan on going to a dyno day middle of next month, so we can finally see what the car actually puts down. Its on a land+sea dyno, i dont know how those compair to mustang, or dyno dynamics as far as being higher or lower.....

Any plans on making a tune for a 300zx maf and bigger injectors? next thing i want to do is a rotated GT3076R turbo and forged internals

Let me know if i should change anything else due to the little bits of knock when full boost is reached at lower rpm's
Thanks Rob

Footnotes: I prob put 10k on the +4 tune, no issues at all, great power, great drivability and decent gas milage.
drove it some more on the +7, the car is FAST.... it pulls from 3200 right to rev limit, the midrange power hits hard with my setup. once i get some more drive time on the +7 ill report back, but the +4 tune is perfect for a 22T/25D hybrid with stock internals and a turbo upgrade, like a 16G.

[evolutionmovement]

When it goes lean under light throttle at cruise, do the temps stay safe (or at least know it doesn't set off the knock sensor)? Because, really, don't you want it to lean under light load for economy sake as long as there's enough fuel enrichment when it transitions to load?

[MikeyMeyagi]

it goes to 18-19 on my wideband, i think its a bad o2 sensor. it hasnt happened for a while now tho, and if it does i just mash on it real quick and it comes out of it.

[cj91legss]

it goes to 18-19 on my wideband, i think its a bad o2 sensor. it hasnt happened for a while now tho, and if it does i just mash on it real quick and it comes out of it.

It's Fine!

[evolutionmovement]

The combustion chambers probably aren't designed for it, but from what I've heard, newer cars will go to around 20 on light load.

[logan9691]

So I wanna know more about swapping over the 20G cams. Was it a straight swap or did you have to change a bunch of stuff to make them work? Have you noticed any improvements in power with them. I have a set laying around and if its worth it I might put them in my 2.5 DOHC heads when it gets time to put them in.

[rob]

heres a copy of my last update to Rob from a few nights ago....

Thanks for the update Mike. I sent some follow up questions in email.

Just for clarification, since Mike explained that his hybrid motor has a lower CR, I made him 3 maps to try; my base EJ20G tune, base +4 degrees advance to the entire ignition map, and a "+7" with up to an additional 3 degrees advance in the high load regions of the knock correction map. So far the results sound great. I am very anxious to see what it looks like on the dyno.

For my updates, I have driven Drew's car with my 4to2 ignition converter and a stock EJ20G ECU for about 100 miles. I think the ignition converter is working as expected however the car isn't running perfectly. It likes to idle a little rough and is a little rough when cruising with very light throttle applied. Other than those conditions, it runs perfect and pulls strong and smooth at WOT. I have a feeling it is the O2 sensor as my EJ20G has these same symptoms when it's o2 sensor went out. It's possible that the G ECU is more sensitive than the 22T ecu and that is why it is new behavior. I thought it might have been my spare Jecs MAF was bad, but I picked up another used one and it didn't get any better. Once I figure this last little bit out, I will build some converters and put my G tune into Drews car to dyno.

-Rob

[kimokalihi]

I've been running Rob's EJ20G ECU and tune in my 91SS with 97 Forester EJ20G complete motor with 520CC STI sidefeeds, TD05 16g turbo, 06-07 WRX TMIC, 3" TBE, lightweight 9lb flywheel and so far it runs perfect! I'm currently using a Hallman manual boost controller set to 16 PSI and it pulls hard 3500+ all the way to 7500RPM. I got 25mpg on my best tank, 23.5 on my worst tank. I've ran 4 tanks of gas through it and I'm about to fill up and see what I get on this tank with minimal spirited driving.

The knock light flashes from time to time mainly if I let off the gas at cruising or going up a hill slowly. I figure it's normal but I'm not sure. It's never flashed that I've noticed during pulls so that's good. AFRs are right at 14.7 on cruise and dip down to about 11-12 full throttle. The car idles perfect, runs perfect. I love it! Rob did a good job and he was very helpful with all the questions I had.

I have not done any launches in the car to try out the 5K RPM rev limiter for launching because I'm scared to break my transmission. But I did put the pedal to the floor while stopped with the clutch in to check that it works and it does.

I would highly recommend a Rob Tuned ECU, especially if you've got an EJ20G motor.

[ericem]

So is there going to be any progress on making the ej22t ecu work with the chip?

[rob]

So is there going to be any progress on making the ej22t ecu work with the chip?

There is going to be.....just hasn't been for a while.

My plan is to finish up my ignition converter work and EJ20G ECU testing first, then move back to working on the EJ22t ecu. I am going to try to fab a few EJ22T rom boards at the same time as my converter PCBs. That could be done as early as next week. Once I have his car running to my satisfaction on the stock G ECU, I will move to my tune and run it through some more testing to see if there are changes needed for the tune. I plan to collect some dyno plots along the way. That's when I will switch focus back to the EJ22T tune. I should have my rom board add-in ready and I can start monkeying around with the stock tune. The majority of the work is still ahead in reversing the code, but I should be able to get to the basic maps in short order....we will see.

In a perfect world you all would convert to G ECUs and I could leverage my expertise there. That is the motivation for the ignition converter; to simplify the conversion process.

I know plenty of people want to stick with a 22t ECU tune for minor mods, so I will keep working on a solution there.

Drew has been kind enough to let me hang onto his "spare" SS for as long as I need. Whatever comes out of my testing, he deserves a lot of thanks for contributing to the development.

-Rob

[SLODRIVE]

You can add me to the list of people converting to the 20G ECU. I recently scored a Z4 ECU, I already have a JECS MAF sitting around, and I'm going to pick up another igniter or an SVX igniter to install it as a wasted spark system, thanks to all who researched it out. Once I get it all sorted out, I definitely want to get it "chipped", although I'm going to hang on to my piggyback for an E85 tune with 550s.

[farfrumwork]

ok, I may start looking for an EJ20G ECU (already have the right MAF and some 550's). I need EM badly, but I can't quite justify an Autronic and would love the PNP of the chipped ECU.

Are there any guidlines to follow when shopping for a 20G ECU? It sounds like there are a few versions(?)
Any ID#'s or serial# ranges to look for? (I hate buying thig twice). Sorry if this is in the thread *somewhere* already.

Thanks

[cj91legss]

there's a list of compatible ecus on page 3 of this thread

[rob]

ok, I may start looking for an EJ20G ECU (already have the right MAF and some 550's). I need EM badly, but I can't quite justify an Autronic and would love the PNP of the chipped ECU.

Are there any guidlines to follow when shopping for a 20G ECU? It sounds like there are a few versions(?)
Any ID#'s or serial# ranges to look for? (I hate buying thig twice). Sorry if this is in the thread *somewhere* already.

Thanks

I have a few spares if you have trouble finding one.

-Rob

[klin7757]

Also, from your pictures I see you have an early Liberty EJ20G ECU. Unfortunately these not tunable. You will need another G ECU for chipping.

-Rob

Could you explain why these are not tunable? I accidentally bought a 20g ecu not realizing it was from a Liberty. It has the chip slot just like the wrx ecu's.

[rob]

Also, from your pictures I see you have an early Liberty EJ20G ECU. Unfortunately these not tunable. You will need another G ECU for chipping.

-Rob

Could you explain why these are not tunable? I accidentally bought a 20g ecu not realizing it was from a Liberty. It has the chip slot just like the wrx ecu's.

It comes down to the actual electronic hardware inside the ECU case. The microcontrollers and companion ASIC chips are different and thus the assembly code to make it run is different. There may be a socket to accept an eprom, but that doesn't mean I know what to do with it

I had one of these to play around with and it was different enough that I gave up.

I stocked up on spare EJ20G ecus, so if you need one, just let me know.

-Rob

[rob]

I don't want to steal Mike's (MikeyMeyagi) thunder, but he just sent me some dyno results from his 2.2t hybrid. I'll leave it to him to post details, but I'll tease a bit by saying the results were better than a cobb stg2 '04 STI

Oh and Mike, if you read this, I tried to send a reply but your email seems to be broken. Do you have another address?

-Rob

[logan9691]

That's amazing! Any ideas on how a 22t with crappy stock heads will do?

-Logan

I don't want to steal Mike's (MikeyMeyagi) thunder, but he just sent me some dyno results from his 2.2t hybrid. I'll leave it to him to post details, but I'll tease a bit by saying the results were better than a cobb stg2 '04 STI

Oh and Mike, if you read this, I tried to send a reply but your email seems to be broken. Do you have another address?

-Rob