Creating my own trans tune

[TheBac]

With all the talk about torque limiting issues and desiring to delete 2nd gear for the track, Ive tried to make a trans tune. This is for the drag strip ONLY...I wont drive it on the street.

Please review and comment on these changes:

Started with BBT stock trans tune, 15184109 operating system, 15183960 transmission ID

I have changed the following:

Comparison summary: 11:40:12 am, Sunday Jul 05, 2009

Calibration comparison between BBTstocktranstune_2ndgearlaunch_.tun and BBTstocktranstune.tun.
*Values that differ by more than 0.100000% are considered different.


D5000 "Part Throttle 1->2 Shift Speeds" 6.8750 "Different from cell: 0,0 to cell: 7,0 inclusive."
D5005 "Part Throttle 2->1 Shift Speeds" 2.7026 "Different from cell: 0,0 to cell: 7,0 inclusive."
D5020 "WOT 1->2 Shift (Speed)" 5.4688 "Different from cell: 0,0 to cell: 3,1 inclusive."
D5025 "WOT 1->2 Shift (RPM)" 50.0000 "Different from cell: 0,0 to cell: 3,1 inclusive."
D5035 "WOT 2->1 Shift (Speed)" 3.9063 "Different from cell: 0,0 to cell: 3,1 inclusive."
D5196 "Torque Limits" -39.3500 "Different from cell: 0,15 to cell: 8,16 inclusive."
H0103 "Final Drive Ratio" 7.3971 "CAL: 3.73 <-> ALT: 4.10"
H0136 "Tire Revolutions Per Kilometer" 1.1191 "CAL: 402 <-> ALT: 424"

The 5196 changes I gathered from the TCM tuning thread. Thanks Tony.
The speedo/tire changes are me changing to 275/70/16 tires and 3.73 gear.

I am not sure on the 2nd gear delete tables. When you are changing the part throttle 1-2 upshift, do you change the entire table (~100 values) to "0" or just the first couple lines? Same question for the 2-1 part throttle downshift table. I think you do them all, dont you? -- otherwise it would confuse the TCM when boosting up?

Is there anything else that needs to be changed? I do have a 2001 TCM stock tune (15175854 OS and 15175857 trans) Should I just start with that instead of the 2003 tune?

Go ahead and rip away....but keep in mind this is my fist foray into tuning....

 

[TheBac]

OK, 40 views, no help. Maybe just stating what I did wasnt enough to get some opinion on if Im doing this right.

Here's the actual tune file...


removed post per user request

:witch:

 

[jpowel29]

I would also zero out all of the part throttle upshift speeds (D5000). Make a few passes with it to see how your truck reacts. Then you can adjust your shift speeds/rpms if needed.

 

[lotsofmiles]

one view was me, and I'm not much help in this area yet. Sorry


I am curious about 2nd gear launches tho

 

[TheBac]

Sorry James. Didnt mean to be rude.

I would also zero out all of the part throttle upshift speeds (D5000). Make a few passes with it to see how your truck reacts. Then you can adjust your shift speeds/rpms if needed.

Thanks J. I figured the whole part throttle table had to be changed.

I noticed the WOT 4-5 shift is set for 110mph and 3275rpm. So how is it the trans will shift into 5th at 80mph and 3400rpm? See why I get so confused?

 

[SDP]

I noticed the WOT 4-5 shift is set for 110mph and 3275rpm. So how is it the trans will shift into 5th at 80mph and 3400rpm? See why I get so confused?

That's not MPH its KMH. I'm no expert on any of this but hopefully that helps you out a bit.

And don't worry, I did the same thing the first time I went in to raise shift points.

 

[RENODMAX]

Tom all I would do is WOT upshifts rpm and mph. If you want pm me your email I'll fire you a model tune.

 

[TheBac]

That's not MPH its KMH. I'm no expert on any of this but hopefully that helps you out a bit.

Oh wow it is. Now that makes sense...110kph is roughly 69mph.

How the hell do I change the values to read English, not Metric?

Tom all I would do is WOT upshifts rpm and mph. If you want pm me your email I'll fire you a model tune.

But if you dont change part throttle too, wouldnt the trans NOT go into 2nd when staging, then jump instantly to 2nd when you drop the hammer? That sounds bad.
I ask because the truck isnt at WOT until the green comes on? Im only at 50% throttle just before launch.

 

[8100 Power]

Oh wow it is. Now that makes sense...110kph is roughly 69mph.

How the hell do I change the values to read English, not Metric?

Go to Edit in the EFILIVE Tune.... Then select Configure Display Units ... Then select the parameter or select all and click imperial.

Hope this helps.

 

[RENODMAX]

What I have helped you out with is good for 1st gear launches. Sorry if that doesnt apply exactly what you are looking for, but plenty of guys are going fast leaving in 1st and its less risky.

 

[TheBac]

Go to Edit in the EFILIVE Tune.... Then select Configure Display Units ... Then select the parameter or select all and click imperial.

Hope this helps.

Thankyouthankyouthankyou! I hate metric.

 

[TheBac]

What I have helped you out with is good for 1st gear launches. Sorry if that doesnt apply exactly what you are looking for, but plenty of guys are going fast leaving in 1st and its less risky.

Hey...Ill take help any way I get it. Only reason Im looking at this option is that I blow thru the brakes on my truck at anything over 2000rpm.

 

[TrentNell]

Tom i cant look at the tune because i dont have my laptop but i did my part throttle 1-2 upshift tables as well that way it would kick up to 2nd as soon as i hit the peddle and i would just stay into it a little the whole time so it wouldnt down shift back to first. i will look it over tomarrow unless you already got it figured out ?

 

[RENODMAX]

Trent knows what he's doin he is the one who got me started trans tuning

 

[TheBac]

Tom i cant look at the tune because i dont have my laptop but i did my part throttle 1-2 upshift tables as well that way it would kick up to 2nd as soon as i hit the peddle and i would just stay into it a little the whole time so it wouldnt down shift back to first. i will look it over tomarrow unless you already got it figured out ?

Thanks Trent. Heres the updated tune after J's suggestion. Tell me what you think.

Removed tune per Tom's request

 

[TrentNell]

Trent knows what he's doin he is the one who got me started trans tuning

i am no expert but have played enough

Thanks Trent. Heres the updated tune after J's suggestion. Tell me what you think.

i'll check it out tommarrow .

 

[GMC_2002_Dmax]

Leave your final drive ratio at 4.10, it will probably get PO'd if you change it to 3.73's

 

[TheBac]

How come? Something to do with shift timing?

Oh, I think I see it....in the shift timing area of the speedo correction parameters...the values are based on 4.10. I changed the other one back to 4.10. That odd they used 4.10 for shift timing when the rear axle ratio is 3.73. Thanks Tony.

 

[dmaxvaz]

Leave your final drive ratio at 4.10, it will probably get PO'd if you change it to 3.73's

in which way Tony? i did that like 6 months ago

 

[GMC_2002_Dmax]

in which way Tony? i did that like 6 months ago

I NEVER CHANGE THAT NUMBER, the few people who I have fielded questions, calls from had terrible shifts when they changed it.

Stock from the factory it is 4.10 on ALL calibrations, so why change it if it works.

Just one more thing to worry about, but you leave yours alone since you have it all fixed up.