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You do know the Corvette has the PE button and circuitry to use PE mode.
The Impala/Caprice/Roadmaster does not, so without fabrications to the circuitry and a switch, PE mode does not come into play when tuning on a non corvette model.
If I’m mistaken please correct me.
Thread necro aside, you are mistaken.
If conditions are met, the pcm will enter power enrichment mode. Can't say I've ever heard of a switch to enable PE.
 

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You do know the Corvette has the PE button and circuitry to use PE mode.
The Impala/Caprice/Roadmaster does not, so without fabrications to the circuitry and a switch, PE mode does not come into play when tuning on a non corvette model.
If I’m mistaken please correct me.
Ok.
Regardless whether it's an LT1 L99 or LT4, or in what vehicle it was originally or is presently installed, or which calibration operates any LT1 L99 or LT4:

LT1 Caprices, Impalas SS, Roadmasters, Fleetwoods, and Corvettes all LACK the Performance Mode switch.
Only some FireBirds & Camaros have the OEM electrical wiring which allows them to access and use the alternate shift table known as 'Performance Mode'.
In trucks & SUVs, although still called 'Performance Mode' inside the calibration, the driver's right hand would find it referred to as 'Tow/Haul Mode'.

Had GM given Cadillac Fleetwoods V4P access to BOTH Normal Shift Mode AND Performance Shift Mode, the V4P's Normal Mode table would have been written so as to score 17city / 25hwy MpG.
Instead, V4Ps scored 15city / 23hwy, which was less than 1MpG away from being branded a Gas Guzzler, because the Normal Mode Table was written to permit towing 7000lbs.

Normal and Performance are Shift Modes. GM did not make the latter shift mode readily available to B- & D- cars, and (if I'm not mistaken) even Y-cars, only F-cars. (Trucks and SUVs are kind of another matter.)
Wide Open Throttle Power Enrichment is a fueling mode selected by the driver's foot when it wants to have fun.
Two separate protocols.
 
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Oh damn. I just noticed the thread date...
I hope you’re all still with us.
Interestingly enough though theres still relevant information and conversation to be had on this old thread.
I was reading some tuning tips that also referenced the B Bodies PE mode as being activated at a TPS position of 98% - 100%. But like Marky said it addresses fueling parameters not shift configurations.
Im just now learning these tuning basics myself, and will always appreciate responses that illicit further discussions...
I have since learned that there are currently datalogging programs out there for the 96-97 OBDII’s
One is TunerPro RT another is an EFI Live program , and ECMProScan, they all require the purchase of a license key to activate them.
From $39 to $169.
But they are currently being used, updated, and customer service supported (To one degree or another)...
But they do live.
Thank you Marky for elaborating further than I can off the top of my head. ?
 

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If anyone knows of any other datalogging software out there for the 96-97 OBDII’s (especially free), please feel free to respond and enlighten me...
 

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TunerPro (and RT) is free, the RT version will prompt you to donate $$$ with a short delay timer is all.
 
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TunerPro (and RT) is free, the RT version will prompt you to donate $$$ with a short delay timer is all.
I don't say this often enough:
TunerPro & TunerPro RT are both free; that said, he (?) deserves our thanks. Please show whatever support you can afford.
… I hope you’re all still with us.
Interestingly enough though there's still relevant information and conversation to be had on this old thread …
That's what the ISSF is for!
… was reading some tuning tips that also referenced the B Bodies PE mode as being activated at a TPS of 98% - 100%.
Like Marky said it addresses fueling parameters not shift configurations.
'%TPS Threshold for WOT vs RpM (Low Temp)' is the table / heading that sets where/when WOT-PE mode activates.
The higher the RpM the moment just before the throttle is whacked, the less throttle whack needed to activate WOT-PE.
In the OEM B-car calibrations:
@ 1600RpM or less, the TPS% must exceed 60% to activate WOT-PE.
@ 4000RpM or more, the TPS% must exceed 30% to activate WOT-PE.

(The OEM coolant temp threshold for the High Temp table / heading is too high / too late for LT1 engines to ever use …)
 

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Thank you DirtyBob.
I appreciate the information and I’ll let you know which platform I choose and review how it works.
I will definitely send either the price of, or any amount of donation that is requested.
If not for their efforts. We wouldn’t have the options (however limited) that we do. I will always financially support and reward the efforts made, to keep these cars up to date and running at their best efficiency possible.
Thank you for your time and effort !
 

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Thank you also Marky for taking over where my knowledge ended.
I don’t know or understand most of the tuning parameters as they apply to the other areas and tables affected or required to engage certain protocols.
I am a newbie to tuning, just to make it perfectly clear to everyone, anything I address is probably more of a question than a factually accurate statement.
And I do know, what I don’t know, which is always the first position to take when learning a new subject matter.
Thank you to all for having patience with me, I do not want to come off as some sort of know it all.
Because I am far from that when it comes to these cars...
 

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Thank you DirtyBob.
I appreciate the information and I’ll let you know which platform I choose and review how it works.
I will definitely send either the price of, or any amount of donation that is requested.
If not for their efforts. We wouldn’t have the options (however limited) that we do. I will always financially support and reward the efforts made, to keep these cars up to date and running at their best efficiency possible.
Thank you for your time and effort !
 

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Excuse the double post.
I lost wireless during posting it and it got sent twice.
I still haven’t figured out how or if a post can be deleted.
 

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It's worth noting that the definition files on the 8051 pcm were reverse engineered by enthusiasts, with little to no support from GM, and mistakes were made. For example in the EEXTRA .xdf file the maximimum line pressure scalar is labeled as psi but we now know that it is actually epc solenoid duty cycles. If you raise the scalar thinking you are increasing line pressure across the board, you are actually lowering it instead. There are other things in there that are poorly documented/understood (EST system time lag comes to mind), point being you want to be sure to keep backups of your .bin files and verify that things are working as expected.
I know that I need to brush up on this stuff as I will have some tuning to do on my own car soon.
 

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It's worth noting that the definition files on the 8051 pcm were reverse engineered by enthusiasts, with little to no support from GM, and mistakes were made.
For example, in the EEXTRA .xdf file the maximum line pressure scalar is labeled as psi - but we now know that it is actually epc solenoid duty cycles.
If you raise the scalar thinking you are increasing line pressure across the board, you are actually lowering it instead.
There are other things in there that are poorly documented/understood (EST system time lag comes to mind), point being you want to be sure to keep backups of your .bin files and verify that things are working as expected.

I know that I need to brush up on this stuff as I will have some tuning to do on my own car soon.
Amazing that after 25 years and counting, TunerCAT, TunerPro, and other individuals whose names I regretfully fail to cite on BOTH sides of the frakken Atlantic, are STILL finding hidden tuneable parameters and keeping IronBlock LT1 tuning alive and kicking.
 
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I couldn’t agree more, and am also surprised some of you are still discovering these anomalies/unknowns and trying to identify them.

I am currently copying all the line items under the ‘Switches’, ‘Constants’, and ‘Tables’ into a .txt file readable in ‘Notepad’ hopefully to be integrated into an excel format where each cell can have ‘Notes’ associated you it to place a brief description of what it does, what other cells it affects, and or need to be adjusted at the same time.
This will be a long slow going project of not only doing all the data input and formatting of the cells and their notes, but also finding out or learning what each adjustable cell actually does, or how it works.
Similar to the way EEhack or $EEhack does...
It is going to take a good amount of time, and input, from a wide variety of sources and folks who know, and can explain what all those parameters are, before I can institute them into the notes that show up when you hover the mouse pointer over the cell.
Probably an overly ambitious endeavor that may very well never be completed, but WTH...
I do have spare time now and then to tinker with the idea, and I know there are many people who would really benefit from such a file, especially people like me, and it would give me the opportunity to learn as many of these parameters and configurations as my aging brain can hold.
It sounds like you would be one of those reliable sources by which your input could be extremely helpful...
Along with several others...
TunerCAT and DST appear to still be all but identical in function and in the graphics user interface...
I suspect so do other tuning programs that are still out there in current use.
Peace ✌? Out...
 
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