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View Full Version : help with tranny tuning for $EE



jrgcjnl
05-27-2012, 09:39 AM
As I was working on my current tune's line pressures and shift times, I noticed that on there isn't a line pressure modifier for 1st gear, and that on the offsets they don't include 1st gear
why is that? can one be made up or am i stuck?

jrgcjnl
05-27-2012, 09:44 AM
the only reason im asking is because i want to have a certain pressure in normal mode but in performance mode i would like the tires to break loose, thanks in advance guys!

Fuzzy from MN1988
05-27-2012, 09:20 PM
I'm kind of in the same place, there's a couple people on Impala SS Forum as well wondering about tranny tuning.

jrgcjnl
05-28-2012, 12:42 AM
also i was wondering, if i post up my tune could anyone review it and tell me if anything is wrong with it? my mods are in my sig

jrgcjnl
06-01-2012, 04:02 AM
...anyone? :innocent2:

EagleMark
06-02-2012, 04:13 PM
Sorry I've been gone for a week.

You can post your bin, I have JET DST software to take a look at the 96 OBDII file.

Playing with line pressures can result in some bad results! There's just way to many factors to take into consideration. What I found to be perfect easy way to tune a 4L60E was start with a caddy V4P towing package bin, use every table for tranny with compare and change them all!!! Or just use the bin in a 94-95 to start, not sure that would work in a 96?

Then look at performance shift times and IIRC they are all 0 while normal has varied times. I copied all performance shift time into normal shift time tables. This was all I needed to have a good performance shift MPH, firmer shifts and felt more like a performance car or truck if you will. Also lowered my tranny temps by 10-15 degrees! You can actually feel shifts and drives very nice instead of the one big slush...

Now if you like the one big slush and want to change to performance when needed there is a writeup here I copied from somewhere giving them credit of course on how to wire in the performance shift button that came on only one car IIRC a Trans AM? But I found no need as I would have just done all that work of wiring in a button just to leave it on always?

I've been told that if you have a shift kit installed in tranny this will result in way to hard a shift... HTH!

As I get my LT1 engine into new unwrecked car I do want to play and learn some more on this. One thing I did learn earlier when I was doing above is trying to change shift MPH times is also a very complicated procedure as so many factors, what happened was on highway my tranny was shifting 4,3,4,3,4,3,4,3 as I did a datalog and did not notice it happening as it was so smooth till tranny over temp light came on! So where I left off and was happy with was the Caddy V4P Towing bin, shift times 0. Poof! Nice!

So great care is needed when making a change to one table as so many other tables are effected. When you make a change or experiment use the data log for tranny to read back what is happening and watch tranny temps.

On a wet day from a rolling 20 MPH start I would get kickdown to first and a little tire spin, when shifted to 2nd tires would break loose and instant RPM redline! :rockon:

jrgcjnl
06-06-2012, 02:31 AM
its actually running on obd1, but here it is
i know its a bad thing but its really addicting and well my trannys wearing out and before i change it to another rebuilt one i have i would like to have a little bit of fun :)
and about the performance button, i have it but programmed as you can see so when i race a stick car he wont jump me :p
and about my tranny its worn out but stock with the vette servo, it was really tame
and i actually really messed with my tranny tables and ive gotta say its working pretty darn well :rockon:
i also installed a dayco tranny cooler so it could also help my coolant be colder as well
and theres something about my 285-40-18 bfgoodrich g-force t/a i dont like, they dont get traction whatsoever, they burn out from anything under 30, and completely go sideways from around 20mph:yikes:
but anyways, thanks in advance and hopefully you guys can let me know if anything is wrong with my current tune

PJG1173
06-06-2012, 06:56 PM
Once you get your new trans built there will be no need to change anything but up/down shift and TCC lock/unlock points. most good performance trans builds mechanically increase line pressures, increase shift firmness, and reduce shift time.

jrgcjnl
06-06-2012, 07:58 PM
It's not really built just rebuilt with better clutches, HD band, and hopefully I'll get a new 2800+ torque converter, and even then you can still up the line pressure, it's not like I have billet servos or a shift kit yet so no problem

PJG1173
06-06-2012, 08:32 PM
it's not like I have billet servos or a shift kit yet so no problem

Like I said in my previous post "once". I understand its fine now. my 4l60e has all you listed and then some. It will bang when it goes into OD and there has been no mods to the tune other than shift points and lockup. the performance shop that built the trans for me specifically said do not tune for what they did mechanically or bad things will happen.