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Premium Member
2006 TBSS 3SS
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17,596 Posts
Discussion Starter #1
Below is a comparison log between a stock SS tune and one that someone has messed with. No details, but just showing the tables that have changed.

In your opinion, what is not good to mess with?

On thing I noticed that I dont see a reason to change is the max knock retard setting. Seems like its there for a purpose and its better of work on KR than cap the amount it can pull.

This messed with tune is no one on this site. Just something I have had laying around for a while.

I am going to start on a new tune. I have the timing cranked up, KR is clean after a couple attempts with the histogram, TM is down to half, PE changed.

Comments from other people tuning their truck?



 

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Premium Member
2007 AWD 3SS
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8,588 Posts
I wouldn't mess with MAF calibration unless you can test it with laboratory flow meters under different temperatures and barometric conditions.
 

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2006 TBSS 3SS
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17,596 Posts
Discussion Starter #3
Good point. As long as there is a good stock MAF table available, I dont see why I need to mess with it. Thats being the tools I have.

I have MAF tables for the 100mm MAF if I decide to go back to that and of course the stock one too.
 

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Premium Member
2007 TBSS
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4,834 Posts
The MAF needs to be recalibrated if you change to any intake.


I wouldn't have changed the injector constant without changing the injectors. Other than that.. make a change and note the difference.. theres no definite right or wrong way to do this..
 

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2006 TBSS 3SS
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17,596 Posts
Discussion Starter #5
Thanks Alvin.

When you say MAF recalibrated I think thats pretty hard to do for the average guy. I have no doubt you could do it sitting on a dyno.

I would think using stock GM MAF tables from a known production car that uses 100mm MAF should be a good start right? Besides I still have a purchased ADM tune that I should be able to steal the MAF stuff from. AFR looked good when I ran it. Well I think it did...

One of the things I am realizing is closed loop can do a pretty good job at covering stuff up. I thought I would try something yesterday and I cranked up the lower temp where closed loop starts so it never would go into closed loop. I got a surprise with AFR at WOT. I did not think closed loop had any effect on WOT but apparantly it does. Doh !
 

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2007 AWD 3SS
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I've also noticed that changing things that take out TM under normal driving, such as Accel threshold and stall torque management, can lead to increased detonation from a more aggressive accelleration.

Something to think about...you have to log and mod for everything...even if it's not directly related to something you are changing.
 

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Premium Member
2007 TBSS
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4,834 Posts
Thanks Alvin.

When you say MAF recalibrated I think thats pretty hard to do for the average guy. I have no doubt you could do it sitting on a dyno.

I would think using stock GM MAF tables from a known production car that uses 100mm MAF should be a good start right? Besides I still have a purchased ADM tune that I should be able to steal the MAF stuff from. AFR looked good when I ran it. Well I think it did...

One of the things I am realizing is closed loop can do a pretty good job at covering stuff up. I thought I would try something yesterday and I cranked up the lower temp where closed loop starts so it never would go into closed loop. I got a surprise with AFR at WOT. I did not think closed loop had any effect on WOT but apparantly it does. Doh !

Not true at all. Take advantage of all those histogram tools HPtuners has blessed you with. Listen, before the days of Hptuners I (and probally ever other tuner) had to build histograms using excel. Do you know how hard that is? I literally have one I used to use on speeddensity Lt1's that would lock the computer up when you hit F7 for it to calulate. You couldn't keep the auto calculate on or else it would drag the computer down. creating a new histogram took hours and hours..

now with hptuners you can setup a histogram for your MAF table and log anything you want on it. the only thing they do not have is std deviations and such but still its an awesoem tool
 

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06 TBSS 2WD
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570 Posts
Thanks Alvin.

When you say MAF recalibrated I think thats pretty hard to do for the average guy. I have no doubt you could do it sitting on a dyno.
I would think using stock GM MAF tables from a known production car that uses 100mm MAF should be a good start right? Besides I still have a purchased ADM tune that I should be able to steal the MAF stuff from. AFR looked good when I ran it. Well I think it did...

One of the things I am realizing is closed loop can do a pretty good job at covering stuff up. I thought I would try something yesterday and I cranked up the lower temp where closed loop starts so it never would go into closed loop. I got a surprise with AFR at WOT. I did not think closed loop had any effect on WOT but apparantly it does. Doh !
On a TBSS with aftermarket CAI (no stock reduction piece) you simply replace the stock TBSS table with another STOCK MAF TABLE from another GM 2006 production car that uses the same motor and MAF. There is no need to custom tweek your MAF (9 out 10 times you screw it up more when you do custom MAF tweeks). Now your 100MM ADM MAF is different, it is more sensitive to position and rotation, that depending on your intake you will have to tweek a stock non-tbss table and it'll take you a while. I actually did an excel spreadsheet to help me expedite the process and with a ton of flashes and tuning I finally got it down to where command AFR is resultant AFR without screwing up part throttle dynamics. If you need help when you put it on, I can get you started to save some time.

No need to screw with the injector flow rate unless you messed up the MAF or changed injectors. If the MAF is dead on, everything else will be predictable at WOT. I only change injector flow rate when I change injectors and I make sure those are as calculated and what they are so everything else is predictable.

TM - ECM or TCM... Why TCM & ECM?
 

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2006 TBSS
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820 Posts
Spark AFR Adder (right above IAT spark on your list).. Whats goin on there. Was it zero'd out? Umm. ok.. Yeah. It looks like it was. 138 of 187 cells.. Hmm.. Put that back to stock.. pull out timing changes you added in the upper cyl airmass part of the HO table.. and redo WOT timing.. I guess if you are not getting KR @ high load part throttle it wouldn't be worth the time. However, there is a reason why timing would need to be different when in PE or not PE. You know?

Oh and watch out with the IFR.. The tuner may have scaled the table so that the car thinks the injectors are smaller than they really are, and dumping more fuel accordingly.. This is a hacky way of adding fuel.. This may also be why your throttle response is bleh. When you really do injectors, the transient fueling usually needs to be modded. Usually..

The correct way to tune MAF would be to disable dyn airflow and run in open loop.. However, I'm pretty sure transient fueling still has a hand in things.. and thats based on the VE table.. Oh, and the open loop fueling table is crazy rich.. The new hpt release will be able to log IVT, which is great for adjusting the open loop eq ratio.
 

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Premium Member
2006 TBSS 3SS
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17,596 Posts
Discussion Starter #10
This is not a tune I plan to run. But I know a few people that are.

Some of this stuff I understand and some of it I dont. So its good to know, dont bother looking at the injector stuff on a bolt-on truck. That was kinda the point of the thread.

And yes, the PE/COT spark advance has been zerod
 
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