749 ( typhoon ) Code in a 730 ECU with a V8

[Jon Fedock]

    Yes, I have gotten this to work. I also had that type of trouble with
mine, but I made a wiring harness from pigtails (junkyard). Here's a list of
differences (from my jumbled notes). These are where I had problems:

    Serial Data is now on pin A9 (I LIKE scantools)
    C10 is not used on 730 (injector driver - move to C12)
    D5 and D6 are tied together on 749 (injector jumper)
    C13 and C15 are also tied together on 749 (injector jumper)
    I used 730 style wiring (I just walked out there and checked) tying D6
and D7 together and grounding them. Interestingly, the 730 I used was from a
2.8 and had "Injector jumpers" and caused the same problem you describe - I
didn't remove them initialy.
    D14 is a EGR input on 749. 730 is 4th gear switch. Not used in my
application.
    There are other differences, but weren't problems for my application.

Standard disclaimers apply. This is what I found to work with 19lb and then
30lb high impedance injectors. 19lb max out at 6 lbs of boost at about 2300
rpms :). Hope this helps.
Jon Fedock
www.geocities.com/jonfedock


----- Original Message -----
From: Gorden Jennings <gjennings at extremenetworks.com>
To: <gmecm at diy-efi.org>
Sent: Wednesday, October 18, 2000 5:44 PM
Subject: 749 ( typhoon ) Code in a 730 ECU with a V8


> Hi All,
>
> Has anyone gotten this to work on a v8, yes I have read the archives and I
> did not see a successful reply, but may have missed it. I am having
problems
> getting this to work. I have set the cylinder number to 8 in the Ty code.
I
> am using the memcal that the anht code came in so my cylinder select
should
> be OK from a code and hardware point of view. This is a 406 SBC V8 that we
> installed TPI using the 730 with the anht code, this worked great. Then a
> Paxton supercharger was installed and we started to tune for it and found
> out the rising rate fuel regulator from Paxton would not keep consistent
> pressure as it was restricting the normal fuel regulator, one day would be
> 42 psi static and the next day may be 38 the next 40. Trying to tune the
> lower end of the scale was becoming a problem. We decided to run the ty
code
> as I have one and have tuned them for my friends also. Installed the code
> with the appropriate changes so it would work on a V8 onto the 730 ECU and
> it would not idle, start then sputter and then die. This would happen no
> matter where the bpw constant was set. I then took my 749 ECU out of my ty
> and got the same result so I do not feel it is ECU related. The anht code
> seems to tickle an area of the code that has to do something with the
timing
> of the code and the Ty code does not. I have just started to trouble shoot
> this problem and was looking for any insight from the list to what
direction
> I should take.
>
> I also have a question concerning the register at location 3ffc. I noticed
> the anht code sets this register value to fb1a and the Ty code set this
> register to eb1a. Does anyone know what this one bit difference
represents?
> Thanks for any replies you may have.
>
> Regards
> Gorden
>
> > -----Original Message-----
> > From: owner-gmecm at diy-efi.org
> > [mailto:owner-gmecm at diy-efi.org]On Behalf
> > Of Carl Ijames
> > Sent: Tuesday, October 17, 2000 8:34 PM
> > To: GMECM mailing list
> > Subject: Re: GN injector offset
> >
> >
> > > Would any of you who are familiar with the GN PCM/bin care
> > to tell me
> > > if it includes an injector offset vs. battery voltage
> > table?  I'm using
> > > a set of stock GN 30lbers (0 280 150 218) in my LT1 and
> > wouldn't mind
> > > updating this data in the LT1 PCM if its readily available.
> >
> > It has both injector offset ($34C1) and pump compensation ($34D3) vs.
> > battery voltage tables.  The pump comp table is a multiplier
> > but is all
> > ones.  The inj offset is in msec and gets added to the calculated ipw:
> >
> > Volts   Offset, msec
> >  0.0     7.78, N=E*32.768 so 7.78=$FF
> >  1.6     7.78
> >  3.2     7.78
> >  4.8     7.78
> >  6.4     7.78
> >  8.0     3.3
> >  9.6     2.0
> > 11.2     1.5
> > 12.8     1.07
> > 14.4     0.82
> > 16.0     0.64
> > 17.6     0.46
> > 19.2     0.46
> > 20.8     0.46
> > 22.4     0.46
> > 24.0     0.46
> > 25.5     0.46
> >
> > In the tech area of www.gnttype.org there is an Excel spreadsheet with
> > most of the data tables, and a disassembly listing with comments.
> >
> > --
> > Regards,
> > Carl Ijames     ijames at netaxs.com
> >
> >
> > --------------------------------------------------------------
> > --------------
> > To unsubscribe from gmecm, send "unsubscribe gmecm" (without
> > the quotes)
> > in the body of a message (not the subject) to
> > majordomo at lists.diy-efi.org
> >
> >
> --------------------------------------------------------------------------
--
> To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
> in the body of a message (not the subject) to majordomo at lists.diy-efi.org
>

----------------------------------------------------------------------------
To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org