I have a 16197427 ECM that has been converted from TBI to PFI Mode can some one explain to me what has been converted . I think the drivers only but not sure what else if any ? Thanks

If running high-z injectors you need to short out the 2 injector driver sense resistors. Install a jumper wire shorting out the .1 ohm resistors.

Adjust the software to run in MPFI mode. I think there was a 3 to 5 CAL locations that needed bits changed to do that. Then adjust the fuel injector constant and offsets appropriately. I think there is one thread around here how to scale the injector constant properly. Some threads have it wrong. After that, tune the spark and VE tables.

I have been running/testing a 427 ECM with a 350ci TPI setup, 4-spd trans.
The only thing I don't like is the adaptive timing algorithm. I started tweaking those constants and tables and have taken a break from it for a while. From memory, it would pull a lot of timing between shifts. I think it is only used when a manual trans. is selected.

What kind of fuel injectors and trans. are you running?

I'am running LT1 injectors flow matched and the L460E trans . I have this set up and running already and i hate the timing something is not right . Why i was asking is because i was thinking of going back to TBI mode , adjust the constants from that point and see how it runs . I'am not sure if i can go back with out it getting modified again ?

If your run in MPFI you need to put the jumper wire on the MEMCAL for starters. Without having it and setting the MFPI in the CAL then it won't run properly. This is why you are having better luck with the TBI mode right now.

Take a look at the "tbi guys it is time to update" or something like that thread created by dimented24x7. The jumper wire on the MEMCAL was discussed.

You need the jumper wire on the MEMCAL for doing the right bank fuel firing.
You need the jumper wires on the injector sense resistors for the high-z injectors.

junkcltr;

I have found and gone through that thread, but can only find repeated mention of "jumpering the MEMCAL/netres". I could not find any specific instruction or diagrams on where specifically on the MEMCAL needs to be jumpered, for cyl select.

Could you provide a direct link or some more specific information?

Thanks

I have found this thread:
http://www.thirdgen.org/techboard/di...-pfi-mode.html ($0D in pfi mode?)

Grumpy mentions shorting pins 13 and 16 together.

Yes, that is the jumper necessary for MPFI mode on the MEMCAL. The software CAL settings should also be set for MPFI. Installing the jumper wire sets the MEMCAL for V8 batch fire mode.

The interesting about the $0D code is that it can be hacked so the jumper wire isn't needed. I learned this from dimented24x7 and reading/modifying the code.

This can't be done with the 747/165/730/749 ECMs. The 427 ECM has the ability to change fuel modes on the fly.

EDIT: Pin 13 should be tied to ground, not connected to pin 16. Pin 13 is the cyl select pin and should be grounded for double fire batch V8 mode. See the Ludis ECM site for which pin is already connected to ground so you can jump pin 13 to it.

The MEMCAL change for the 8cyl "cyl select" would be the same though for use in a '7730 style ECM, correct?

I'm interested in modifying some of my 6cyl MEMCALs for use in V8 projects.

Yes, grounding pin 13 of the IC will make the ECM fire the injectors every 4th DRP. This is know as double fire batch mode for a V8 engine.
It will make your V6 MEMCAL fire the injectors at the proper rate that the code expects. The limp home values will be off and the knock ckt will not have he right values unless your v8 has the same bore size as the v6.

More info here:
http://www.thirdgen.org/techboard/di...49-memcal.html (730, 727, 749 Memcal Info Needed)