stupid 7727 question

[dusterbd13]

ive got 3 empty ones on the shelf that I never labeled. none have a memcal in them.

so, how o I tell which one was my v8 one? does it even matter? am I just screwed?

also, any way to test them to make sure that the ecm itself is still good prior to starting to tune with it? I remember having some trouble with bad ecm's on the original drivabeater.

[RobertISaar]

every 7727 is identical to every other 7727. the MEMCAL you stick into them will determine what they will run.

as for testing.... you would need to build a bench to test all of the inputs/outputs to be 100% certain. that's not a short process(I probably spent ~16 hours on mine) and may not expose any intermittent faults that might come up in a real vehicle.

[dusterbd13]

ok. cool. thanks!!

any reason I need a stock v8 memcal? ill be going full custom tune with a moates adapter.

[RobertISaar]

you'll need it for the knock filter and NETRES, otherwise the ability of the ECM to detect knock is going to be severely compromised(and either end up with a lot of false knock being detected or no knock activity able to be detected) and you can adjust cylinder count on the NETRES via a jumper or resistor(I forget which), but if you're already needing the correct knock filter, you'll have the correct NETRES as well. or at least close, once you start modifying stuff, the limp-home mode calibrations that use the NETRES are already going to be off.

alternatively..... if you got ahold of a correct external knock filter, you can modify the MEMCAL to allow that to operate correctly. one of the Australian guys from delcohacking has also put together a programmable knock filter(which is similar/identical to how the ~98+ GM OBD2 PCMs manage their knock sensor(s)), which is also pretty neat.