new $EE tuning thing!

[kur4o]

I tried to sniff GM OEM tool, mode4 for line pressure, but it did Park/ Neutral check first.
At my test bench I couldn`t lie PCM, it`s in P/N, so I couldn`t see how it controls the pressure.
For safety reason you can add that check before Line pressure control is enabled.
I am not sure what will happen with transmission if you play with line pressure at gear or car is moving.
So put some big warning on it.

Also during the sniff I made, the OEM tool sends f4 56 08 command before any f4 56 01 mode request and some times add f4 57 07 09 [which I have no idea why]
Maybe it can add to more stable connection at b/d body setup.

[steveo]

yeah I'm going to add a big "disable safeties" button since I also plan for static timing advance in the next release which is also super dangerous

[lionelhutz]

As long as you don't lock it out using the C15 P/N input because I didn't connect it. I think the Tech testing was supposed to be done in park.

The problem with doing it when driving would be locking in a high current or low pressure which could cause slipping and quick transmission failure. A high pressure should just cause harsh shifts, well maybe extra wear or broken parts if you did it all the time.

[steveo]

any results or feedback on the line pressure thing?

[lionelhutz]

I'll be trying it out on the weekend.

[kur4o]

I tested it on static enviroment.
It does seem to work. The minimum value should be positive, at least $01[otherwise it switch to default calc].
It does change the value of CURRENT TORQUE SIGNAL PRESSURE.
From this value and trans temp through 3d table is calculated actual ad current value.

[steveo]

i've committed changes to github that effectively change line pressure into a percentage (X/255*100) with a minimum of non-zero... not sure if that's what we want, but it's better than 0-255 for display?

no new beta yet, though.. i'll get the egr thingie done tomorrow then release another beta. doing these controls that override other controls take a bit o' work to ensure all use cases function, but i did the same thing with AFR and cyl drop, so no big deal

just lettin' you all know im still working on it.

i think my next project (aside from eehack) might be trying to get an lt1 ecm running as a standalone with a more traditional distributor input of some kind on a non-lt1 engine. it's a fun ecm but i don't see it used outside of LT1s much, even though spares are plentiful due to so many crashed and ruined b-bodies in the wrecking yards. i'll try to find a distributor and play with it on my bench. might be a long shot but fun to try. not sure if i can use the existing opti inputs or have to use another ad channel

[steveo]

oh and i would like to thank spfautsch, i now have four y-body users using the new beta and it seems to be working well, so we have corvettes nailed, we need to get b-body tested but im excited that we're finally hitting non f-body cars...

[lionelhutz]

LOL, I was going to get back to you on what 0-255 meant force current wise, but you jumped the gun and made a new scale. I do appreciate the addition and I will get to testing it soon. I think the most accurate end result will be scaling it to represent the force motor current.

It'll really be nice to be able to verify line pressure without trying to watch a gauge while driving the car WOT.

[johnny_b]

i think my next project (aside from eehack) might be trying to get an lt1 ecm running as a standalone with a more traditional distributor input of some kind on a non-lt1 engine. it's a fun ecm but i don't see it used outside of LT1s much, even though spares are plentiful due to so many crashed and ruined b-bodies in the wrecking yards. i'll try to find a distributor and play with it on my bench. might be a long shot but fun to try. not sure if i can use the existing opti inputs or have to use another ad channel

I would be heavily interested in this. The optispark is one of the LT1's major reliability weakpoints. ive looked into it only barely.

Seeing as how you have a fondness for antiquated abandoned engine platforms, have you ever considered developing anything for the early Northstar V8 engine? some of the early ones used ACDelco ECU's. Even though it is a Gen III PCM like the LS series engines, it is a platform that has been left out to dry entirely. To my knowledge there is no program that will even simply flash these or even XDFs for TunerPro in existence either. I feel these engines have a lot of potential and the junkyards have lots and lots of them.

I would be willing to supply some ECU's

[Thatdudeorion]

i think my next project (aside from eehack) might be trying to get an lt1 ecm running as a standalone with a more traditional distributor input of some kind on a non-lt1 engine. it's a fun ecm but i don't see it used outside of LT1s much, even though spares are plentiful due to so many crashed and ruined b-bodies in the wrecking yards. i'll try to find a distributor and play with it on my bench. might be a long shot but fun to try. not sure if i can use the existing opti inputs or have to use another ad channel

As a corollary, I think lots of guys with LT1's would be really interested in a way to economically drop the optispark in favor of a traditional distributor. There's a few options out there now with Delteq, LTCC, and the various 24x conversions but damn can they get pricey, particularly the 24x conversion since you need a new ecm and tuning suite's that are definitely not free.