Tuning for new injectors

[Bruce Plecan]

I had 30s and went to 40s.
I did have a couple bins to work with, but
  Basically changed the injector from 29ish to a little less then 40, and
then played with the idle speed tables, and AFR to CTS table.  The changes
were very slight to the CTS table, but I took the idle speeds way down.
Also set the max IAC count down some.
Maybe not the ideal way to do it, but I've got the results I want.
Maybe the voltage offset, is related to ecm and it's drivers?.
Bruce
    Course I cheated some...


> Well, I finally got around to installing my GN 30lb injectors this
> morning along with updating the injector offset vs. voltage table in
> my LT1 PCM to the one from a GN.  The good news is that the used
> boneyard injectors work just fine.  They only required some xylene,
> a set of new O-rings and some paint to look just like new again.  They
> also brought my WOT pulsewidths back to a reasonable level (19ms at 6000)
> The bad news is that its going to take some experimentation to get the
> injector offset table right.  Here's the scoop-

> With the GN injectors (0 280 150 218) installed, FP set to 45 PSI,
> injector constant set to 29.9 and GN offset table programmed, the
> BLM's stay near 128 at idle, but the car starts VERY hard.  Its getting
> too much fuel during cranking and needs to be put into flood-clearout
> mode to start up.

> When I switch back to the stock LT1 24 lb offset table, the car starts
> much better, but the BLM's skyrocket to 160+ at idle and return back to
> 128 once I give it a bit of throttle and get the pulsewidths up.

> So, what I need to do is combine the cranking offset from the LT1
> injectors (say, less than 10V or so) with the operating voltage offset
> from the GN injectors (at say 12V and above).  Anyone have any advice
> on how to do this a bit more cleverly than just guessing, but without
> having to pull the injectors back out to actually measure it?<g>
> -Scott

----------------------------------------------------------------------------
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