[Gmecm] More '730/$8D tuning questions...

Fri Apr 20 11:02:08 UTC 2007

AXXC is a decent calibration to start with.  Did you load it into the emulator or into a chip?  Is the checksum calculation disabled in the calibration which works (mask ID set to $AA)?

Large plenum intakes tend to like more pump shot.  Sometimes surprisingly more.  Other than that it's the same old game of finding the correct VE and timing by trial and error.

Zaphod

-----Original Message-----
From: clair.davis at charter.net
To: gmecm at diy-efi.org
Sent: Wed, 18 Apr 2007 9:24 PM
Subject: Re: [Gmecm] More '730/$8D tuning questions...

I've got some more comparing to do tonight.  I uploaded the lightly-tweaked
AXXC when I got home from work, and it almost instantly turned on the
CEL/SES/whachamacallit light, so I couldn't get an idea of how it would even
idle.  Swapping in the untouched AXXC did the same thing, but it cleaned
right up when I reloaded the bin I was driving with last weekend.  I
couldn't even get the ALDL to synch up until the last bin was loaded.

Once I get a bit more sorted out, I'll need to pick your brain on the finer
points of tuning with a large volume short runner intake.  That's
essentially what I have on my 340, one of the Mopar Performance M1 series.
I've also got a large direct-linkage 4V throttle body that I'm going to have
to work with, too.  PE and SA ought to clean those up, though.  And good
point on the TPI intake, I forget how well it worked.  The early Chrysler
long-ram and short-ram engines would generate over 100% VE even back in the
day, but I don't think they were as much of a treat off idle.  I'll keep
that in mind.

Clair

----- Original Message ----- 
From: "Mike Wilson" <mwilson at bwarch.com>
To: <gmecm at diy-efi.org>
Sent: Wednesday, April 18, 2007 10:26 AM
Subject: RE: [Gmecm] More '730/$8D tuning questions...

> Clair, it sounds like you are on the right track with what you are
thinking.
> A fairly stock program for a TPI F-body is probably a good starting point
> for a lot of older muscle cars to use as a base program. The Vette
programs
> are too aggressive and fine tuned for their application to make them easy
to
> retrofit into another application.
>
> The TPI intakes have a lot to do with the high VE numbers. The velocity
they
> generate gives amazing amounts of low end torque. They run out of steam
> really fast but low end is fantastic. This is great for a street car but
not
> for racing. Most TPI powered cars end up highly modified if the owner gets
> into drag racing, like mine. I eventually ended up running a Victor Jr.
> intake that I converted to fuel injection. My big valve 409 inch small
block
> was just too much even for the best of the aftermarket TPI intake parts
that
> I tried.
>
> Good luck with the tuning,
> Mike
>
> -----Original Message-----
> From: gmecm-bounces at diy-efi.org [mailto:gmecm-bounces at diy-efi.org] On
Behalf
> Of Clair Davis
> Sent: Tuesday, April 17, 2007 7:28 PM
> To: gmecm at diy-efi.org
> Subject: Re: [Gmecm] More '730/$8D tuning questions...
>
> Thanks for that suggestion, Mike, that's an interesting looking bin.  The
VE
> curves have a very similar character to what mine could/should be on the
WOT
> end, but it still floors me that VE can be so high in the idle range -
over
> 60 at 800rpm!  My lean-best-idle appeared to be in the low-mid 40's, but
> that may make sense with my low 8.5:1 CR.
>
> I'm tempted to just tweak the injector & cylinder specs, tone down the
spark
> advance table, and give it a spin.  If I'm thinking about this right,
having
> the VE's too high just means I'll tend rich with the INT/BLM's again.  If
it
> runs like crap, at least I have some confidence that it hasn't been
monkeyed
> with too much before I got it.
>
> Clair
>
>
> ----- Original Message ----- 
> From: "Mike Wilson" <mwilson at bwarch.com>
> To: <gmecm at diy-efi.org>
> Sent: Tuesday, April 17, 2007 11:29 AM
> Subject: RE: [Gmecm] More '730/$8D tuning questions...
>
>
> > Clair, with a manual transmission & iron heads the best way for you to
get
> > started is to use the 1992 5.0 liter 5-speed Camaro bin AXXC and copy
the
> > VE, PE, AE & cold start up info from the 350 auto AUJP bin into the 305
> bin
> > plus change the cylinder volume & injector flow rate and disable VATS.
> >
> > You may want to pull more timing out because of your data logging on
your
> > specific engine but this should get you a lot closer to a drivable
engine
> to
> > start with. With a good manual transmission iron head base program you
can
> > then tune for your cam and headers and modify the rest of the program to
> fit
> > your application.
> >
> > I did this when I put a T-56 into my 91 5.7 TPI Z/28 and it worked very
> well
> > but my engine was otherwise stock so I only had to deal with the manual
> > transmission issue.
> >
> > Hope this helps,
> > Mike
> >
> > -----Original Message-----
> > From: gmecm-bounces at diy-efi.org [mailto:gmecm-bounces at diy-efi.org] On
> Behalf
> > Of Clair Davis
> > Sent: Monday, April 16, 2007 8:38 PM
> > To: For discussion of GM EFI hardware and software
> > Subject: [Gmecm] More '730/$8D tuning questions...
> >
> > ... 3) Is there a benefit to using a different base cal, such as ANHT
vs.
> > AUJP or whatever, as long as they're for essentially the same family of
> > engines?
> >
> > Thanks in advance as usual, and I really am glad to be able to drive
this
> > old girl again, as frustrating as it is at the moment.
> >
> > Clair
> > 69 Plymouth Valiant, 340+730
> > Fort Worth, TX
> >
> >
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>
>
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