JamesLinder Ive tried the tune you had received from PACT and Its not working out to well will my truck. Can someone take a look and guide me on things that need changed???
Seems like it is still bogging pretty bad when it shifts to 4th. Think I might have to raise that up a touch. Maybe raise all the shift points up a touch.
Good morning Sarg. Sorry to hear you are still having problems.
It is common to adjust the shift points upwards over stock for the higher gears depending on your final gear
ratio. A little trial and error you should be able to home in on what works best for your set up. Just like
engine tuning, each vehicle is indeed unique. I personally would not have my converter lock up until after
the shift from 3rd into 4th (that is, until a higher speed is reached beyond where it shifts from 3rd to 4th).
If your converter is remaining locked during this shift and adjusting the speeds does not fix the problem then
try unchecking the enable converter lock during shifts to see if this works. With an unlocked converter, I
do not see how it could bog shifting from 3rd to 4th with your high stall speed. Let me know what you find
out.
Is this transmission original to your vehicle? Just wondering if your transmission is responding to what the
PCM is telling it to do; I have not had a chance to see what quirks occur when upgrading an F-Body or other
vehicle from 4L60E to a 4L80E.
Last edited by JamesLinder; 03-10-2014 at 06:24 AM.
Texas GM08, good morning. I will look at your file this morning, however could you please tell me what you mean when you
say it is not working well? Please be specific what is not going well with shifting, etc. Thanks.
TexasGMC08, I would probably return all torque reduction settings for the transmission (not the engine) to stock settings.
Same for shift pressures. If you have a built transmission the increased shift pressures incorporated into the build itself
should provide you with more than adequate pressures, and modifying the table settings could increase these beyond what
is reasonable for shifts at TPS positions less than WOT, especially just cruising and light load shifts. Torque reduction only
operates for a very brief instant just prior to shifts, and offer the protection necessary to give you longevity on your
transmission; they do not impact your elapsed times enough to be worth shortening the life of your transmission build and
can often also result in hard shifts at cruise and light load conditions. Your transmission builder, if a good one, is your best
source of recommendations. I destroyed no less than a half dozen transmissions before I learned what works best. I am
certain you can obtain extremely good WOT shifts without doing away with torque reduction completely.
Just fyi, RPM Transmissions builds the best GM automatics that can take all the punishment you can throw at it.
I also have found PATC of Bossier City builds extremely good transmissions however their quality control is hit
and miss, and their customer service (availability to talk on phone) both before, during and after your unit is
build is somewhat poor. In addition, they seem to do their best to wiggle out of delivering on their warranty.
They built my current transmission which performs quite well and is very durable because I went with manual
shift valve body that removes the problems with the electronics fighting the mechanical over the time required
for shifts which is what causes most problems burning out the clutch packs. Also, you can downshift at your
preference and then stomp the gas instead of the other way around with fully automatic which also causes a
lot more wear and tear and shock on the internal components. Going to manual shift valve body also makes
your vehicle a 100 times more fun to drive in my opinion. I would never switch back. B&M pro-stick is awesome
shifter when doing this modification.
I have a stock trans with a 3600 stall added its a lock up conv.,since adding it the trans acts a little funny,and bucks between shifts can anyone give me advise on how to tune trans ,will it cost me a credit to get a tune off here
james im having probl also cant get my shift rpm to work right,i have a stock trans with hd2 shiftkit and a 3500 stall 3.90 gear and 26 tall tires heres my tune, also need some help with my engine tune I only run 94oc fuel want it to shift at 6000 rpm,lt,ory,lid,filter,no cats,ported maf,tb.... its shifts at 6450 I cant seem to get it to change ive tried to lower mph and rpm
Attached is Excel spreadsheet analysis of your transmission's shift calibration assuming you have stock gear ratio's in yours.
If you have opted for the close ratio 1st and 2nd gear ratio's, let me now and I will post the revised spreadsheet to account
for this.
Basically, your transmission has been tuned not to shift into 4th gear at high throttle positions to avoid tearing up the 3-4
clutch pack, meaning that you have to let off the throttle when you want the vehicle to automatically shift into 4th gear
at higher speeds on the highway. You might try putting your shifter into 3rd (which you should always do when you bang
on it hard), and then manually shifting into 4th gear when you want the car to do so. I believe this will over-ride the table
values and shift into 4th gear at the time you move the shift handle regardless of the throttle position (even if TPS is wide
open, 100%)Shift Calibration - Jay Eckelbarger.xlsx
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