advice needed for definition files with modded l35

[Airbrush guy]

Hi all,
I have a 95 astro 4.3 cpi that Ive recently changed heads on (now 96 vortec) and also done the marine intake mod so have external injectors. Im looking for tuning files and have used the $0d and can get bswx bin to connect in tunerpro but ecm has bsww on the label (16197427) and has lower sticker of 16231855 bsww. my aim is to fine tune as the conversion worked well and using adjustable fpr it is somewhere near using mercruisers bosch 24lb injectors running at 3bar and timing still set to 0degrees base and egr deleted.

I wondered if anyone else had done this before as know some s10 owners have before turbo mods and any help with finding appropriate definition files would be appreciated as just learning this side of things

Thanks
Gary

[dave w]

The link to $OD information: http://www.gearhead-efi.com/Fuel-Inj...Information-0D

Injector Firing vs Distributor Reference Pulse (DRP) can be challenging. I'm thinking TBI injectors are being fired once every DRP. I'm thinking Port Fuel Injection (PFI) is once every 3rd DRP for a V6 engine and once every 4th DRP for a V8 engine. Pin 56 on the Memcal is the cylinder select voltage for TBI or PFI.

Possibly using a 1227727 ECM or 1227730 ECM with a V6 PFI Memcal is an option to achieve the correct Injector Firing vs. DRP (cylinder select voltage)? Possibly the cylinder select voltage of a $OD V6 TBI Memcal can be modified (with a resistor) for correct V6 PFI cylinder select voltage?

Then again, why or why not have all six injectors firing once every DRP with a TBI Memcal?

dave w

[Fast355]

The link to $OD information: http://www.gearhead-efi.com/Fuel-Inj...Information-0D

Injector Firing vs Distributor Reference Pulse (DRP) can be challenging. I'm thinking TBI injectors are being fired once every DRP. I'm thinking Port Fuel Injection (PFI) is once every 3rd DRP for a V6 engine and once every 4th DRP for a V8 engine. Pin 56 on the Memcal is the cylinder select voltage for TBI or PFI.

Possibly using a 1227727 ECM or 1227730 ECM with a V6 PFI Memcal is an option to achieve the correct Injector Firing vs. DRP (cylinder select voltage)? Possibly the cylinder select voltage of a $OD V6 TBI Memcal can be modified (with a resistor) for correct V6 PFI cylinder select voltage?

Then again, why or why not have all six injectors firing once every DRP with a TBI Memcal?

dave w

His van was CPI using one TBI style injector in the center of the spider.

[dave w]

Hmmmmm; I thought the post indicated the engine was upgraded to Vortec heads (96) and Marine Intake with 6 Individual Injectors?

dave w

[Airbrush guy]

Thanks , original spec was cpi , had to change to vortec heads to use the mercruiser manifold and as cpi is one injector to six poppets I wired all 6 seperates so all use the same pos and neg so batch firing as you thought initially mercruiser uses 4bar fpr but was way too rich so installed adjustable and 3bar is rich but runs fairly well and have been like this for a while as using lpg too, injector multiplier will need to be changed so gussing multiply 24lbs x6 to get overall figure for cpi injector sizing ? will I need additional hardware to change values?
Thanks

[dave w]

Interesting, all six individual port injectors being triggered on / off at the same time. Hmmm, I don't think that is how the 2.8 / 3.1 / 3.4 liter V6 engines had their six individual port injectors triggered on / off?

I think it would be a good plan to trigger the 4.3 Marine Intake with six individual injectors just like GM did with the 2.8 / 3.1 / 3.4 V6 engine, once every 3rd DRP.

dave

[Airbrush guy]

I believe that every 3rd drp is how the cpi was triggered anyway so these individuals are fired the same way as the cpi originally was but just need to compensate for the increased size and of course better flowing heads and disable egr . Ive looked around for the bin file for bsww but to no avil however bswx does let me connect and will log data but when trying to save after udating egr or injectors it shows errors , so wondered if just need a different bin but struggling to find 95 l35 cpi

thanks
Gary

[dave w]

dave w

4.3 CPI Files.JPG

[Airbrush guy]

thanks dave , the bswx at the bottom of the list you linked is the one that connects but then errors that's why I was looking for bsww as that's whtas stated on my pcm (middle section according to gm)

Thanks again gm info pcm.jpg