F1/F77 scaling

[Maxtor]

Does anyone know why the MAP scaling used in Promgrammer and Tunercat are different for these two tables? Not that it really matters, but the MAP values displayed in Tunercat are one bar lower than Promgrammer. I generally work with Promgrammer, but recently have been using my Tunercat and Romulator more often.

Just curious if anyone knows what is behind this.

Also, I think Dig was working on a patch to increase the resolution of the F77 table. Has anyone used this patch and does it work?

 

[BillC]

Re: F1/F77 scaling

Does anyone know why the MAP scaling used in Promgrammer and Tunercat are different for these two tables? Not that it really matters, but the MAP values displayed in Tunercat are one bar lower than Promgrammer.

That's because Promgrammer is designed to handle both 2-bar and 3-bar chips. It automatically switches between the two display calibrations, based on the presence or absence of BG's 3-bar code. The definition file you're using for Tunercat is only set up for 2-bar, and so only displays 2-bar column headings. If you want a 3-bar calibration, you'll either have to get another definition file or make your own.

 

[Maxtor]

That makes perfect sense, Bill. Now I understand. Thank you for the reply.

 

[turbodig]

Re: F1/F77 scaling

Does anyone know why the MAP scaling used in Promgrammer and Tunercat are different for these two tables? Not that it really matters, but the MAP values displayed in Tunercat are one bar lower than Promgrammer. I generally work with Promgrammer, but recently have been using my Tunercat and Romulator more often.

Just curious if anyone knows what is behind this.

Also, I think Dig was working on a patch to increase the resolution of the F77 table. Has anyone used this patch and does it work?

<ObFredDryerQuote>

It works for me!

</ObFredDryerQuote>

It helps a bit to get that fuel bog out of the 80-130 kpa range.
I've got it on 4-5 trucks now.

I've kinda abandoned it to work towards eliminating it entirely and going to a full-resolution VE table. Also will eliminate the need for F30.

Later,

Dig

 

[Maxtor]

Re: F1/F77 scaling

[quote="turbodig
I've kinda abandoned it to work towards eliminating it entirely and going to a full-resolution VE table. Also will eliminate the need for F30.
[/quote]

LOL - I would have figured YOU got it to work, Dig! I didn't realize you visited the board very often so I was wondering if a code change to get more out of F77 was out there. Jim (Leroy) sent me some information a while back but my hard drive crashed since then and I lost his message.

Your new plan sounds like FAST, that could really help speed up tuning! Are you still planning on incorporating F29 and F29E? Please keep us posted on what you develop.

I never understood why GM created such a complicated formula to derive fueling... It doesn't seem like it would need to be so hard?

 

[turbodig]

Re: F1/F77 scaling

[quote="turbodig
I've kinda abandoned it to work towards eliminating it entirely and going to a full-resolution VE table. Also will eliminate the need for F30.

LOL - I would have figured YOU got it to work, Dig! I didn't realize you visited the board very often so I was wondering if a code change to get more out of F77 was out there. Jim (Leroy) sent me some information a while back but my hard drive crashed since then and I lost his message.

Your new plan sounds like FAST, that could really help speed up tuning! Are you still planning on incorporating F29 and F29E? Please keep us posted on what you develop.

I never understood why GM created such a complicated formula to derive fueling... It doesn't seem like it would need to be so hard?[/quote]

After looking at a bunch of different GM stuff, I've formulated a few theories on the "why".

#1 - Space. Takes fewer bytes to run the two RPM tables that are there.
They weren't really worried about ease of cal. Gotta remember, this is
back in the days when 128K ROMs were large... in '86.

#2 - Code re-use. GM cut-n-pasted parts from earlier code, less develop-
ment time that way.

Later,

Dig