Tuning question for 730 ECM

[gcwestph at erols.com]

Shannen Durphey wrote:
> 
> Tim,
> 
> Are you sure it's only a speed related TCC apply?   What happens if
> you disconnect the VSS?
> Shannen

I've seen the same thing in my '87 IROC and a friend's '91 Z28 using a
scan tool while making 1/4-mile runs.  Watched it both in rpm and TCC
lock-up command.

Greg Westphal
'87 IROC

> timsiford at hushmail.com wrote:
> >
> > Blade,
> >
> > That is the Mandatory Torque converter lockup point. No matter what ...
> > the ECM commands TC lockup at that MPH. If you plot your Vehicle Speed you'll
> > notice that the speed still increases even though your RPMs drop.
> >
> > The newest TC calibration file has a setting in the ECM Constants section
> > called "TCC Unlock Prevention Speed Threshhold". That should be the mph
> > that you see your RPMs dropping. Only problem is ... even if you bump up
> > this setting it doesn't seem to work  I verified that TC is using the correct
> > BIN addresses. They are 100% correct ... but, I think that I am still seeing
> > lock. Modify this parameter to a higher mph ... like 115mph. Burn a new
> > chip and then try again. Let me know if it works for you.
> >
> > Tim
----------------------------------------------------------------------------
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