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2006 Red Jewel AWD
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Discussion Starter · #1 ·
Pretty much for Joe at LeftCoast32... anyone who knows can chime in...

I pulled the ECM fuse as directeed, it was out for 25-30 minutes. The TB was acting strange and not dropping off RPM's at first (usually when I get off the throttle, the engine starts to compression brake...not with the LS7 TB), but it seems to have gone away now.

My transmission kickdowns have changed and arent kicking down when I am used to. I seem to be having a little bit or torque loss (floating) from 4500-redline similar to what I had before I corrected the VE tables.

Anyone want to help???
 

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2006 TBSS
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How are you guys adjusting the VE table when very few people know a damn thing about them? Theres all sorts of crazy shit going on there. Its not like the old LS1 VE table.
 

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2006 Red Jewel AWD
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Discussion Starter · #3 ·
How are you guys adjusting the VE table when very few people know a damn thing about them? Theres all sorts of crazy shit going on there. Its not like the old LS1 VE table.
I have a lot of information from a genius LS2 guy and I've done a lot of research with help from Ross and Paul and other people I trust. What are the hidden issues I should be worried about?

I only make small adjustments to the VE Tables and adjusted all the related Airflow tables...

The only problems I'm having now is at sea level, I have that torque float that I got rid of at high elevations by doing the VE Corrections...
 

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The computer is learning the throttle body and does that with some vehicles not all. It is probably due to the tuning as far as the cam and all. Give it a start-up cycle or two and it will learn the new airflow characteristics of the throttle body. The VE tables should not change unless you are no longer using the MAF.
 

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I have a lot of information from a genius LS2 guy and I've done a lot of research with help from Ross and Paul and other people I trust. What are the hidden issues I should be worried about?

I only make small adjustments to the VE Tables and adjusted all the related Airflow tables...

The only problems I'm having now is at sea level, I have that torque float that I got rid of at high elevations by doing the VE Corrections...
I am pretty sure the VE table runs through a series of complex math equations for correction and prediction.. I would love to be able to tune my VE table correctly.. Have you had success disabling the MAF? I hope so as that is the only way to properly tune VE (at least on LS1).. You could use Marcin's spreadsheet to mess with it.. What wideband are you using?
 

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06' TBSS 2WD
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The computer is learning the throttle body and does that with some vehicles not all. It is probably due to the tuning as far as the cam and all. Give it a start-up cycle or two and it will learn the new airflow characteristics of the throttle body. The VE tables should not change unless you are no longer using the MAF.


so you're saying, that I can install an LS7 TB, and that my aftermarket tuned ECM will learn the flow characteristics of it? If so, I might go ahead and upgrade my intake setup to this TB and make it 4" all the way. :)
 

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Left Coast.. When you say learning.. you mean fuel trims, correct? A new maf and a Ls7 TB would definately need some calibrations..The MAF table tells the pcm how much air is coming in at a certain freq and the pcm then adds the appropriate amount of fuel to achieve desired afr. On the stock tune, this is done past 3600rpm.. Otherwise its a very confusing blend of VE and MAF fueling.

The thing is.. the LS2 VE table will change with the weather so easily.. so its very hard to 'tune'..
 

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Left Coast.. When you say learning.. you mean fuel trims, correct? A new maf and a Ls7 TB would definately need some calibrations..The MAF table tells the pcm how much air is coming in at a certain freq and the pcm then adds the appropriate amount of fuel to achieve desired afr. On the stock tune, this is done past 3600rpm.. Otherwise its a very confusing blend of VE and MAF fueling.

The thing is.. the LS2 VE table will change with the weather so easily.. so its very hard to 'tune'..

I never said anything about changing the MAF and it will learn. A new MAF should always be scaled so that it is sending the right airflow data to the computer. The throttle body is learned through the MAF. The MAF reads the airflow and thus changes things to optomized the base calibration. The ramp rates are just a little different and that is where you feel the difference in the pedal.

It is best and easiest to use the MAF as it will give better drivability over Speed Density Tuning. The new MAF's are so much better then the old LS1 MAF's that you dont need to get rid of it and SD Tune anymore.
 

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2006 Red Jewel AWD
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Discussion Starter · #9 ·
I am pretty sure the VE table runs through a series of complex math equations for correction and prediction.. I would love to be able to tune my VE table correctly.. Have you had success disabling the MAF? I hope so as that is the only way to properly tune VE (at least on LS1).. You could use Marcin's spreadsheet to mess with it.. What wideband are you using?

I have had a lot of calculating and some LS2 genius' working on this and I have had great success so far with what we have done. Like I said before, most of what we've done has been associated with the Airflow Tables and only slight correction with the VE. et me look back and see what exactly we did with the VE and I will let you guys know...I can recall at the moment exacty what we did.

PM me your email and Ill send you my .tun file of the most current tune in my SS...


Steve
 
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