LBZ: Defueling on Lbz

JoshH

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I'm going to have to disagree with you on this one, Kory. The LBZ will defuel more on a big tune than on a stock tune. From what I've seen, the ECM uses tq based fuel to control defuel, and unless you alter the tq based fuel table, the defuel can get pretty nasty on bigger tunes depending on how the pulse width and tq based fuel tables are setup.
 

DuramaxPowered

Pushing my luck....
Jan 27, 2008
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There is a way around it, it's not perfect at all all TPS% but It can be made to shift very clean and quick with little to no perceptible defuel even on large tunes.

:thumb:

Tony is right. I am running his tunes with 100% overs and it shifts really nice at all throttle positions.

sent from my LG "Stupid" phone, using Tapatalk
 

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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I dont seem to have a issue with the 6 speeds there easy to get dialed in imo but the 5 speed has kicked my ass (im probably just retarded and not doing something simple right)

Probably :D. Mine has a few hiccups if i drive like a grandma all week, then decided to nail it but after two run, it shifts perfect every time.
 

Harbin_22

Active member
Dec 4, 2010
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I dont seem to have a issue with the 6 speeds there easy to get dialed in imo but the 5 speed has kicked my ass (im probably just retarded and not doing something simple right)

I had his tunes on my 40's and it was the same. Mine is fine at WOT, usually the worst is aggressive part throttle. Say between 50-75%
 

SSchmi5519

LLY Cult Leader
Oct 19, 2008
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I had his tunes on my 40's and it was the same. Mine is fine at WOT, usually the worst is aggressive part throttle. Say between 50-75%

I might try locking the converter at a little lower throttle % then. Probably lots of slip going on there...
 

DIESELMAFIAPER.LB7

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Jan 17, 2010
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I had his tunes on my 40's and it was the same. Mine is fine at WOT, usually the worst is aggressive part throttle. Say between 50-75%

whos robs or korys?? i make my own tunes??? or i missed what you meant lolz :D



Probably :D. Mine has a few hiccups if i drive like a grandma all week, then decided to nail it but after two run, it shifts perfect every time.

shove it :D ya mine will never learn right anymore just loaded stock tune lolz wow talk about turbo lag:roflmao: but it hung wot shifts horribly :confused: also were the **** are pids for the trans?? or is there any ive never tried to log the trans before:eek:
 

JoshH

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There is a way around it, it's not perfect at all all TPS% but It can be made to shift very clean and quick with little to no perceptible defuel even on large tunes.

:thumb:
Are you saying you can't make it perfect at all TPS%? If so, I disagree. It just takes some time driving and datalogging.

I had his tunes on my 40's and it was the same. Mine is fine at WOT, usually the worst is aggressive part throttle. Say between 50-75%

That is exactly what I was referring to in my post. Aggressive part throttle is where it seems to be the worst and bigger injectors tend to aggravate the problem and make it worse. It can be fixed though.
 

GMC_2002_Dmax

The Still Master
Are you saying you can't make it perfect at all TPS%? If so, I disagree. It just takes some time driving and datalogging.

That is exactly what I was referring to in my post. Aggressive part throttle is where it seems to be the worst and bigger injectors tend to aggravate the problem and make it worse. It can be fixed though.

Define Perfect.

:hug:
 

JoshH

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Stock level defuel on the shifts. In my opinion the stock shift quality is pretty much perfect.
 

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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whos robs or korys?? i make my own tunes??? or i missed what you meant lolz :D





shove it :D ya mine will never learn right anymore just loaded stock tune lolz wow talk about turbo lag:roflmao: but it hung wot shifts horribly :confused: also were the **** are pids for the trans?? or is there any ive never tried to log the trans before:eek:

you have to validate all pids after you got it all hooked up through the TCM and loggable pids should become availible. we had to do that to brians to log his trans
 

DIESELMAFIAPER.LB7

<----new hotness
Jan 17, 2010
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ya going to do that now think i know why it hung so bad on stock tune my tcm shift points are at 3400 rpm well after 3250 in the tbiq table rpm it goes from 87mm to 20mm thats the issues im sure so i made 3400 87mm and 3600 78 mm flashing it in see what it does
 
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bluessmax

Tabasco Injected!
Nov 4, 2010
1,143
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Lake Charles, la
I'm going to have to disagree with you on this one, Kory. The LBZ will defuel more on a big tune than on a stock tune. From what I've seen, the ECM uses tq based fuel to control defuel, and unless you alter the tq based fuel table, the defuel can get pretty nasty on bigger tunes depending on how the pulse width and tq based fuel tables are setup.

We have gotten them to shift really nice with leaving tq based fuel alone... We modify it slightly to go full fuel along with Pedal position to deired tq, but we do not modify past what the allison can calculate. The defuel from big pulse will come to how it is ramped up to the "big pulse" if the ramp comes on too strong then where it goes back down for the factory defuel will be too much and yes, it will defuel. So how uS is set up has to be addressed for shift quality as well.