thanks to the forum, i've pretty much got the car to do what it needs to.

There's a small bug - when i'm at highway speed (65-75) and accelerate, the RPM's drop off but then almost as quick jump up, like the TCC is told to engage but then PE comes in and acceleration fueling begins?

 

What are the tcc based settings as far as load and tps %?

Or is it a fuel stumble?

 

not sure if fuel stumble - i've got a couple of carb'd cars, and it doesnt feel like a 'quadrajet bog' type of thing. It actually feels like the TCC is engaging, like an RPM drop.

the tcc numbers are at home, will get them later this eve. thanks orr!

 

started from the '89 AUJM Bin:

*Min Load limit for TCC Lock, Low speed: 3.13% TPS
*Min Load limit for TCC Lock, High speed: 19.92% TPS
*TCC Min Load limit hysteresis: 1.17% TPS
*TCC Min Load Limit High/Low speed thresh: 45mph
*TCC Lower Load Limit vs. Speed (Low Gears): [MPH/%TPS] 12/.39, 20/.39, 28/7.81, 36/24.22, 44/38.28, 52/50, 60/59.4, 68/65.2, 76/69, 84/71, 92/72, 100/73
*TCC Upper Load Limit vs. Speed (Low Gears): [MPH/%TPS] 12/1.2, 20/8.2, 28/32.4, 36/46.5, 44/57.8, 52/67.6, 60/73.4, 68/78.5, 76/80.5, 84/80.5, 92/80.5, 100/80.5
*TCC Lower Load Limit vs. Speed (High Gear): [MPH/%TPS] 12/.39, 20/.39, 28/12.1, 36/29.3, 44/45.3, 52/59, 60/76.2, 68/99.6, 76/99.6, 84/99.6, 92/99.6, 100/99.6
*TCC Upper Load Limit vs. Speed (High Gear): [MPH/%TPS] 12/.9, 20/9.4, 28/24.2, 36/50, 44/66, 52/86, 60/99.6, 68/99.6, 76/99.6, 84/99.6, 92/99.6, 100/99.6

Hopefully these numbers are where the problem is, but if not, let me know what else I can get for you. Thanks!

 

When you are at highway speed, you in 4th gear? Converter should be locked right? Then you roll into gas to accelerate but not going wot are you?

 

yes - i think its like you said, 4th, locked, roll into pedal but not wot

 

If its already locked it shouldnt be having a rpm drop like its trying to reengage lockup. It should open up if gas is pressed hard enough and feel like it downshifted.

Curious what the timing table looks like in those areas and at what engine load this occurs

 

thats whats NOT happening, unless I floor it!

I could try modding the parms that affect that behavior ... any guesses as to which ones?

 

I would guess the upper and lower limits in high gear? Mph vs tps %. Looks like it requires near 100% tps to unlock when in 4th?

Really dont want to accelerate too much in 4th, you want it to kick down to 3rd.

 

Great insight! you're making a lot of sense.

 

I have not played with those tables so not exactly sure but its something i would first look into. I dont recall having any issues doing mild accel from 4th gear. It usually downshifted right away or unlocked if i got too heavy into the throttle

 

I went back to all the AUJM tcc parameters. I was trying to up my mileage, but I suspect that tweaking the stock numbers wont improve mileage that much (of course, that's a guess). And the car runs much better, no hesitation at speed and lockup occurs just as God and GM intended. thanks again!