TPI 350 with V6 Memcal - fuel mod quetions

[74blazertpi]

Well I got this truck from a friend who put a lot into it but couldn't quite get the EFI kinks worked out. Not a mechanic, but he paid enough to get a good one. :(

I got an ALDL cable , chip adaptor and chips with a burner from Moates.

Once I got tunerpro loaded up and downloaded my installed chip I discovered the MEM-CAL which includes the CAL-PAK and PROM (correct?) was not at it was not $8D AJUP but a $A1 BAUC which is for some v6 application.

I burned an eprom chip with a factory tune for $8D AUJP. I installed it in the adaptor with the factory CAL-PAK. Truck runs better. But its not there yet.

Looking some more I found an old thread on thirdgen.org - V6 Memcal mod to run in V8.

it seems to indicates that it isn't good enough to burn a new chip I need to also modify the MEMCAL/CAL-PAK like this.

12124 credit to TUNED PERFORMANCE for the pic.
Note the addition of the small blue wire or jumper.
Pin 1 is in the top right of the MEMCAL pictured, 66 is the lower left. Even pins are on the bottom counting down as you go left to right.
The jumper connects pin 62 (a ground?) to pin 56.

Specific questions are ...

Am I speaking the correct language here?

Is this the fuel mod I need?

Why? Because my MEM-CAL is from a 60 degree V6 and it now needs to adjust fuel timing because I have a 90 degree V8?

Will this clear my CODE 41 - Cylinder Select Error?

Is there even more I need to do? if so would it justify the cost of a factory AUJP MEMCAL $200-300?

I'm going to warm up the soldering iron. Let me know.

[delcowizzid]

I just cut the 15k resistor leg off the netres works perfectly

[74blazertpi]

Thanks for the reply. That makes sense electrically.
That seems a more elegant solution.

Too bad I already put in a jumper on my memcal.
Well actually on my chip adapter for now.

So I can answer a few more of my questions.

It was the fuel mod I needed.
Prior to this mod my engine would run like crap after a certain point missing, loss of power. Probably above some rpm, it wasn't related to vehicle speed.
I could let off the gas and it would run better again.
Now it runs much better, clear out to WOT.
It did clear my code 41, no CEL while running at all. So i'm stoked.

I am still wondering if there are any other differences with the memcals that I need to be aware of?
Is my modded v6 memcal as good as an original v8 memcal?
limp mode? Should I even care about that?

[delcowizzid]

Limp home mode should still be good enough to get off the road out of harms way but it's not really made to drive far on.the mod just let's it know the number of cylinders beforehand it would of had different ignition timing on all cylinders and not correct fuel calculations .

[Six_Shooter]

There are no timing calculations in LHM. LHM uses base timing and the LITTLE bit of advance built into the ignition module. Once LHM is induced the ECM no longer pulls the bypass wire to 5V, so the only spark timing is where the dizzy is set, which is important to have this somewhere where the engine will run without ECM controlled advance, if you think LHM will be needed.

As you have found out the jumper mod works. I've done it a few times now, most recently two days ago for a 1936 Ford, that has a 5.7 TPI engine installed. It had a Street & Perfromance "tuned" MEMCAL in it that was based on a proper PFI V8 MEMCAL by the looks of it. I didn't want to mod that MEMCAL and didn't want to give up my one F-Body TPI MEMCAL, so I modded a V8 TBI MEMCAL (because it had the correct knock filter, and TBI and PFI cylinder count select are different).

I have used V6 MEMCALs in the past in the same way with good results as well. I haven't tested the LHM side of it on the V6 to V8 modified MEMCAL vehicles, but would imagine that unless there's a HUGE change in injector size and/or MAP sensor that the car should at least run enough to get off the road. I know using an N/A MEMCAL for LHM with a boosted application where a 3 BAR MAP sensor is used doesn't work so well. lol Replacing with a MEMCAL from a similar boosted app did allow the engine to run in LHM though, because I did test that one after the fact.

IIn some reading I've done recently it seems that LHM will be less of a concern using the flash based EEPROMs that we use today over what was used back when these ECMs were new. The failure rate of the flash chips is much lower than the E/PROMs had.

[57 Handyman]

Where (site or listing) can I check BCCs so the MEMCAL I have is for a V6 vs V8?

[stew86MCSS396]

If you can't find it here:http://www.gearhead-efi.com/Fuel-Injection/forumdisplay.php?20-GM-ECM-Bins-TunerPro-Definition-Files-Wiring-Diagrams-Tuner-Info!

...seem to recall a forum member that has a reference listing them all..perhaps Google.

...and presuming that the memcal has been unaltered, perhaps you can read the PROM with Moates HDR1 (http://support.moates.net/hdr1/), open with TP and verify number of cylinders. Then you could be a contributor to the above link by contacting a moderator to have your bin added.