[Gmecm] Buick 3300 LG7 MAF Program...

Mon Nov 12 22:11:17 UTC 2012

Robert......

I was thinking about at least a friend's Fiero. He has one of those rare DOHC head conversions of the Patty Duke that he got a while ago when Pontiac made them.  That engine could run either the GM waste spark setup or possibly a distributor.

I also myself have a non-GM application in a Lotus Europa.

Both engines are capable of 7500 rpm, and the ECM I was thinking of using would be a 1227749 version (has two injector drivers and can run 4 low-Z injectors).

Hank

-----Original Message-----
From: Robert Saar <robertisaar at yahoo.com>
To: gmecm <gmecm at diy-efi.org>
Sent: Mon, Nov 12, 2012 5:03 pm
Subject: Re: [Gmecm] Buick 3300 LG7 MAF Program...

as long as the ICM/distributor creates a 2X signal(for a 4 cylinder, 3X for 6, 4X for 8), then i don't see any reason why it wouldn't. just don't try natively driving more than a single low-impedance injector or up to 8 high-impedance injectors on an unmodified PCM. the injector driver's don't like that at all.

what 4 cylinder do you have in mind? the only one i can think of that this excludes would be the quad4 due to the injectors, though i may have an acceptable workaround for that other than outright replacing the injectors.

--- On Mon, 11/12/12, dozierhc at aol.com <dozierhc at aol.com> wrote:

From: dozierhc at aol.com <dozierhc at aol.com>
Subject: Re: [Gmecm] Buick 3300 LG7 MAF Program...
To: gmecm at diy-efi.org
Date: Monday, November 12, 2012, 11:24 AM

Robert...

Can your nAst1 code work with a four-cylinder, or is it hard-coded for only the V6 (60 degree) GM engines.
Some of the modifications you have done, especially the VE and MAF seem to be ideal for running on a four cylinder engine.

Thanks,

Hank

-----Original Message-----
From: Robert Saar <robertisaar at yahoo.com>
To: gmecm <gmecm at diy-efi.org>
Sent: Sat, Nov 10, 2012 8:41 pm
Subject: Re: [Gmecm] Buick 3300 LG7 MAF Program...

and here's the quick run-through of the MAF HZ calculation.

3FC6 (only used in this subroutine) - no actual purpose other than to grab value and compare it to itself to see if 3FF8 should be grabbed again
3FF8 (only used in this subroutine) - stored to AA
double byte 11A - old AA value. gets loaded, then inverted via NEGA/NEGB, A rounded, then AA added to it, then stored to AE
double byte AA - current 3FF8 value. copied to 11A(delta?).
double byte AE - is AA + inverted 11A
double byte 11C - old AC value. loaded, inverted, A rounded, AC added, compared, then divide with AE
double byte AC - current 3FC6 value. copied to 11C(delta?).

11C is inverted, then AC is added to it, compared against a few values, then the divide with AE, creates 16-bit Hz X 1

now, the two big hardware locations are 3FC6 and 3FF8, both of which i've noticed in A1 already, so that's good news. in the 2E hack, 3FC6 is noted as "PA2 counter", so it is a pulse accumulator. it now makes sense how all of these values are intertwined. 3FF8 is also used in 2E in basically the same manner as well. the 2E PCM(used in 94-95 3.4DOHC W-bodies is basically an underhood version of the 94-95 3100 A-Body PCM) is also a P4 unit, so all of this is checking out quite well.

also, the AE XDF that is floating around on the internet? it's not quite accurate.... not sure where it came from, but from the couple of things i've specifically looked at, there are some changes that need made to be correct. the MAF tables were one of them. $AE is limited to 256 grams/sec (2E is limited to 512 grams/sec due to having a MAF table scalar and offset).

--- On Sat, 11/10/12, David Allen <davida1 at hiwaay.net> wrote:

From: David Allen <davida1 at hiwaay.net>
Subject: [Gmecm] Buick 3300 LG7 MAF Program...
To: "David Allen" <davida1 at hiwaay.net>, robertissar at yahoo.com, "GM-ECM" <gmecm at diy-efi.org>
Date: Saturday, November 10, 2012, 11:29 AM

Hi Robert. Attached are 2 .bin files. My chip reader wouldn't auto-detect the chip size, so I read it as a 27C256 and as a 27C512. If these are not usable I can adjust and read it again. Normally it auto detects the chip size, so I hope this doesn't mean the chip was corrupt or damaged.

This MEMCAL (AXAT 9713) was installed in the 8706 ECM I got from junkyard from a 90's Cutlass Ciera 3300 car.

Hope this helps you to improve your nAst1 code MAF function! Will be interested to hear what you find.

Sincerely,
David 

-----Inline Attachment Follows-----

_______________________________________________
Gmecm mailing list
Gmecm at diy-efi.org
http://lists.diy-efi.org/mailman/listinfo/gmecm

_______________________________________________
Gmecm mailing list
Gmecm at diy-efi.org
http://lists.diy-efi.org/mailman/listinfo/gmecm

-----Inline Attachment Follows-----

_______________________________________________
Gmecm mailing list
Gmecm at diy-efi.org
http://lists.diy-efi.org/mailman/listinfo/gmecm

_______________________________________________
Gmecm mailing list
Gmecm at diy-efi.org
http://lists.diy-efi.org/mailman/listinfo/gmecm

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.diy-efi.org/pipermail/gmecm/attachments/20121112/590f7832/attachment-0001.html 