Tune help -- 6.2L 2011 Sierra

[tompat]

Hello everyone,

New to the forum and new to the gas job tunes as well. Just traded in my duramax for this 2011 sierra denali 6.2L. So far i love it but after the test drive i could tell it needed a tune bad. So as i love learning new stuff here i am!

Just looking for tips, tricks, and data you guys may have.

Here is what ive changed so far. In addition to this id like to tune in my high octane spark table since this truck is pretty rich out of the box. Looking at adding 2 degrees and adjusting as i find KR.

Fuel>Power Enrichment>Parameters ---

Change P.E. Mode delay RPM Bypass to 0
Chance P.E. Mode ramp in fuel to 2.0


Electronic Throttle>Throttle open rate limits ---

Change first gear to 100
Torque Control>Parameters ---

Change throttle tip-in torque reduction torque to NO

Speedometer>Speed limiter>Parameters ---

Change speed limiter to 199mph

Change limiter source to ECM

[5FDP]

A good transmission tune will pretty much set you up the rest of the way.

And by good, I mean like you really only need to change quickness of shifts and it'll feel a ton better. Though you can go way more indepth if you wanted, will just take extra time.

[03sierraduramax]

If you set your PE ramp in to 2.0 then I would change your PE ratio, I believe at some points in the stock PE it reaches 1.32ish, which is fine with the factory slow enrichment rate but with 2.0 it would instantly reach it. I would think 1.18 would be a good starting point. although without a wideband its just a safe guess.

[Area47]

change your speed limiter back to stock. if you do not have a customer built drive shaft, or two piece ds you will destroy the shaft.

[tompat]

Thanks for the suggestions guys. I will change back the speed limiter to 100 and look into adjusting the ramp in down a little.

What are you guys doing for your high octane spark? The stock high octane table had up to 6.4KR so I'm adjusting that along with adding 2 degrees to the rest of the table. How far are you guys going before you get KR just about everywhere?

Also for the TCM I increased the shift time by 20% in every gear. Is that similar to what most are doing? I was debating going another 5% but wanted to do some research first. Other than that I changed pressure to the performance option, and turned down the TM a touch. Anything else?

[MStefak]

If I recall correctly the knock happens athigher rpm 4500 Ish. The sensors are extremely sensitive in the gmt900 platform. Do a little reading on desensitizing them. That will pretty much clear that up.

The PE is also super rich outta the box , but you'll need a wide and to get that right.

The transient fueling tables have a bit to offer off the line snap , as does the actual throttle body. I'd look into changing it to remove the " hesitation" that you'll always feel. When I have my laptop up and going again I'll post the part number.

When It comes to the 6l80e there are a few things to be played with.

Shift times, shift pressure and shift torque factors make a huge difference. Once again I'll post something with the laptop.

good luck

[tompat]

Thanks, I didnt know that but almost positive now that it is false KR. Im getting an average of 5.5KR between 4000 and 5500 at WOT even though i lowered those tables a few degrees from stock. I am going to add 10% to the knock sensors in those areas and do another data log tomorrow to see what i find. If all goes well i will add my timing back in and go from there.


Does anyone know why even at full throttle my TP % is only about 83% or so? Could be normal i guess but i wasnt sure.


Also what are you doing for shift pressure? Ive got everything down pretty good with the 6l80e except for this. Some more pressure during WOT shifts would be nice.

['09SS]

83% is basically wide open to the computer, that's the most you'll see

[MStefak]

A run a but higher pressure , helps quicken the shift . But truthfully most of the feel comes from moving the torque management around and changing the shift adders.

83 is the most you'll see because the pcm reserves the other 17% for idle I believe. 83% is wot though.

[warriorpluto]

If I recall correctly the knock happens athigher rpm 4500 Ish. The sensors are extremely sensitive in the gmt900 platform. Do a little reading on desensitizing them. That will pretty much clear that up.

The PE is also super rich outta the box , but you'll need a wide and to get that right.

The transient fueling tables have a bit to offer off the line snap , as does the actual throttle body. I'd look into changing it to remove the " hesitation" that you'll always feel. When I have my laptop up and going again I'll post the part number.

When It comes to the 6l80e there are a few things to be played with.

Shift times, shift pressure and shift torque factors make a huge difference. Once again I'll post something with the laptop.

good luck

Sorry to bring up an old thread, but anyone know what kind of throttle body he may be talking about? I'm trying to atleast get 13s at the track stock with a couple bolt ons on an 07 Yukon Denali

[GHuggins]

He was most likely talking about an old trick to make the throttle more reactive off the line by making the tb size in the tune about 20 percent smaller.

[Area47]

i went 13.3 with headers and an intake on pump gas in my 10 2wd truck. was in the 12's on corn and more aggression with it. 13's can be done with the awd models, just have to be aggressive with it.

[warriorpluto]

He was most likely talking about an old trick to make the throttle more reactive off the line by making the tb size in the tune about 20 percent smaller.

oh ok got you. thanks

[warriorpluto]

i went 13.3 with headers and an intake on pump gas in my 10 2wd truck. was in the 12's on corn and more aggression with it. 13's can be done with the awd models, just have to be aggressive with it.

man great times. what kind of intake you had?

[NotSure]

Thanks, I didnt know that but almost positive now that it is false KR. Im getting an average of 5.5KR between 4000 and 5500 at WOT even though i lowered those tables a few degrees from stock. I am going to add 10% to the knock sensors in those areas and do another data log tomorrow to see what i find. If all goes well i will add my timing back in and go from there.


Does anyone know why even at full throttle my TP % is only about 83% or so? Could be normal i guess but i wasnt sure.


Also what are you doing for shift pressure? Ive got everything down pretty good with the 6l80e except for this. Some more pressure during WOT shifts would be nice.

Try logging burst knock as well, to make sure that is not being included in your total knock retard. I had a bunch of that bogging me off the line, 2013 L94. Now I am looking at the main timing chart, stock chart needs some work. Just wish I had some massaged charts to reference. Seems like stock comes in aggressive at too low an rpm and then backs off too much.