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im looking for volunteers to help in small ways with the ongoing efforts to break open the code in $EE (1994-1995 LT1) a bit.

this hopefully will result in some neat parameters and code hacks that will help get the most out of these ECMs, as well as a better understanding of some of the parameters already available.

i can tell you that there are tons of useful parameters out there that are not accessable or well understood yet, and tons of modifications that could be made.

ever noticed some cars wont stop blm splitting? unstable trims with longtubes or lopey cams? mysterious lean CL idle that you can't work around? getting weird timing behavior? highway lean cruise ability for better fuel economy? getting weird trims and unpredictable PE results with E5 or E10 fuel?

we might be able to make some of those things figured. or maybe not.

this is a volunteer thing and all results will be open and available for free, maybe you'll get a better running car out of the deal, maybe not.

no, you dont have to read any code or know how computers work...

looking for:

test pilots for new features

if you own a 1994-1995 lt1 and have an aldl cable, and dont mind screwing around a little bit, you can help.

test results and see how parameters and code patches react to different types of engine builds. for example i only have a mild cam manual car, i need to determine how parameters react to larger cams, different headers, automatic transmissions, different driving styles, etc.

tuning knowledge itself isn't really necessary at all; but the hardware to read and write bin files and datalog is required.

donations/loans

loan/donate functioning 1994-1995 ecm(s).

i'm broke and right now i only have one, it's in my daily driver, and i'm going to FRY those proms if i keep flashing it for testing every little change.

maybe someone has one laying around as a spare, i've spent hundreds of hours helping people with their lt1 problems, so i dont think a donated ecm is too out to lunch..
 

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Discussion Starter #3
in case anyone is interested or if it helps get any interest, my hit list for the next month is:

- find/test the stoich AFR config to help accuracy in both open and closed loop with blended ethanol fuels (i dont have ethanol where i live, but still...), also patch to output the target AFR for datalogging.

- better understanding of the newly discovered o2 sensor variables (which deal with o2 sensor reaction time, i.e. distance of o2 from exhaust valve, as well as instantenous corrections that happen before INT), and how to best tune them for more accurate BLM fueling with long tube headers and big cams

- make M6 cars use both of the available idle speed tables, switchable with a fake p/n switch, so you can have two idle speed targets on a toggle. this is just a toy, but in my case i figure i can have maybe a sleeper config with a higher idle, and a much lower 'show off the lope' idle.
 

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I'd love to help out Steveo.
I'm still several months from getting the motor back in though, so as soon as I can i will.
I fried my original PCM and got a spare of Ion Soltan of madz28.
I got spare eproms and a programmer but didn't get the PCM socketed like I should have done.
Does anybody still supply PCM's like this ( I seem to recall madz28 don't mod them anymore but havn't contacted him ).
I think frying the PCM is my biggest fear although I'd have to upgrade to something newer/better then.

As a side question... Is there an easy way to setup a second rev limiter that could be switched on/off (cool if somebody else gets to drive my car )

Cheers
Mitch
 

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Discussion Starter #5
if you have an M6, sure!

rev limiter selection should actually be a really easy side project once i figure out my idle selector, for which i plan to re-enable the checking of all the gear selector pins anyway (they seem to be skipped right now if you run a manual bin)

then i'd just need to dick around with that fuel cut code a bit so it doesnt ignore it on a manual trans

A4 already has two rev limiter settings, one for 1st gear, one for 2nd+, so really, you'd just need a fake 1st and 2nd gear on a toggle to make it work.

i might be able to get fancier and just enable that entire table some other way too, ac pressure or oil temp input maybe, but that might be a stretch

shoot me a pm with some skype or email or whatever contact info and we'll give it a shot
 

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Steveo
I have TunerproV5 Red Devil cable. I also have Scan9495. I am running a transplanted 93LT1 running a 95 PC and a M6 trans. My PC is pretty fresh so I am not to worried about flashes. It's also a secondary driver my Primary is a CBR1100XX blackbird.
So if you need a test mule I should have the overfueling problem sorted out this weekend and able to run tests for you and learn some things in the process
 

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good luck on your project guys I'd help yeah out also but I'm OBD2.

Get to learn tunercats next month. Have the chance to get into tunercats from a fellow member on here. So I suppose there will be a learning curve with cats.
 

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Hi Steve
Have you got any further with this yet.
My motor is back in. Still got a few Jobs to do yet but it runs. Just wired the ewp up today.
A few weeks probably then I can start tuning.
Thanks
Mitch
 

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Hey Steveo, I'm in. See sig for build details. The Manual Trans PCM has dual rev-limiters also, one for first gear and another for the rest.

How many times is too much for re-flashing the PCM? I've done mine maybe 20 times in the last month. Is that bad?

I've finally adjusted my MAF calibration, I brought the lower hertz down about 7-3% and the upper ones up about 4-9% that helped a ton!

I have noticed appreciable driveability and torque under the curve by messing with the two O2 settings you listed on your how to website for LT1 PCM tuning. Even the tone of the exhaust sounds meatier with adjusting those delays.

I do still have the BLM slpit issue (decent size cam). I need to get a thermometer and check each cylinder for temp and trim each cylinder.

I can get you data logs and a copy of the respective tune so you can see what I have done so far and the effects it's had.
 

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Discussion Starter #11
The Manual Trans PCM has dual rev-limiters also, one for first gear and another for the rest.
no, it doesnt. there's no way for the ecm to know what gear it's in with a manual trans as there's no sensor for that, so it only uses the first rev limiter table.

How many times is too much for re-flashing the PCM? I've done mine maybe 20 times in the last month. Is that bad?
nobody knows the answer to that, i've flashed over 200 bins to mine and it's still ok.

I've finally adjusted my MAF calibration, I brought the lower hertz down about 7-3% and the upper ones up about 4-9% that helped a ton!
yep, that's about typical for modified intake tract and a cam!

I have noticed appreciable driveability and torque under the curve by messing with the two O2 settings you listed on your how to website for LT1 PCM tuning. Even the tone of the exhaust sounds meatier with adjusting those delays.
can you provide any details on what you adjusted and how much?

I do still have the BLM slpit issue (decent size cam). I need to get a thermometer and check each cylinder for temp and trim each cylinder.
what are your iac counts, what throttle body are you using, and how much have you enlarged the idle passage?

I can get you data logs and a copy of the respective tune so you can see what I have done so far and the effects it's had.
cool, please do!
 

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no, it doesnt. there's no way for the ecm to know what gear it's in with a manual trans as there's no sensor for that, so it only uses the first rev limiter table.



nobody knows the answer to that, i've flashed over 200 bins to mine and it's still ok.



yep, that's about typical for modified intake tract and a cam!



can you provide any details on what you adjusted and how much?



what are your iac counts, what throttle body are you using, and how much have you enlarged the idle passage?



cool, please do!
How does skip shift know not to engage when you start off in 2nd gear??....

I added 50mv to the O2 Swing Voltage and increased the INT Delay by 250%.

IAC counts are at 54. But my latest data log showed the BLM's to be close to each other now varying from 126 to 131 at idle. I think the BLM split is gone....

I sent you a PM with my e-mail address.
 

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Discussion Starter #14
Steveo
Just looked at your EEX files and you've listed it as version 1.7. I'm guessing it should be at 2.7
yeah my versioning got messed up. the one on the site is the most recent.
 

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I will gladly help with this. Ill shoot you a pm with my Skype.
 

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I have been doing some datalogging the past few days with the adjusted parameters. You want me to email it to you steveo?
 

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Discussion Starter #17
sure, lets have a look!

i've been taking a break from lt1 stuff; so haven't really dug into the code much unfortunately
 

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PM me your email. I dont think I have it anymore.
 
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