Darn BCM's Help needed asap please

[V8 Calais]

Hey guys,

Just did a V6 to V8 conversion on a VR, put a VR SS ECU and engine wiring harness into to the car and the engine cranks etc but has no injector pulse (99% certain its the BCM stopping it).

Now cause im using a VN gearbox which is non-electronic can I put a VN ECU and vn engine harness and connect that up to the VR interior loom as the VN's didn't have a BCM so therefore should by-pass the BCM code required?

Any help would be great.

Cheers.

[Ben]

of topic, but how hard of a conversion was it to do ?

[V8 Calais]

Honestly not that hard. We just sourced all the parts and had them on the ground ready to go prior to pulling appart the car (minimizing downtime).

Don't forget you'll need a V8 K-frame, all the air intake bits and pieces, radiator.

Steering racks are the same, i have a feeling we even used V6 power steering lines (slightly modified).

Tailshaft was a different length, can either shorten the V6 one or just get a V8 one.

If you have any questions lemme know. Only thing we haven't done is changed the aircon over to work yet.

[Darren]

so you want to drop a VR V8 into a VN Strati ? You could run the VR ECU, but you need someone to disable the VATS in the memcal or wire up a bcm bypass box and I there's a few differences in the wiring harnesses that could give you a few headaches as well. As you've discovered they won't So easier to stick with the VN ECU.

The engines are the same - main difference is just the 02 sensor which should still work with the VN ECU.
I've got a VR engine in my VH with modified VR harness, I was running the Delco 808 VN ECU in it until I got the Kalmaker SP3

[V8 Calais]

Hi Darren. No this is on a VR commodore it was a V6 and I fitted a V8 5ltr from another VN and its gearbox also but used a VR SS V8 engine harness and ECU but its not getting injector pulse which im putting down to the BCM.

I am thinking about putting a VN ECU (which was with the motor) and a VN engine loom into the VR commodore as i am hoping that will bypass the BCM. Cheers

[Darren]

ah ok
should be no problem getting the engine running. Might need to do a few adjustments on the VN harness, but shouldn't be any major dramas. Just remember there is a anti-theft wire on some VN's as well (depends whether it's a Calais memcal). Just need to connect it up or you'll be in the same situation.

I'm not 100% sure though if there will be any probs with the dash though. VN's ran the speed sensor wire via a divide by 5 circuit in the instrument cluster. I'm fairly sure the VR did away with it, so it might throw the speed input out - I don't think it will affect the speedo though. Might just have to play with some of the wiring if there's any probs.

[V8 Calais]

Hey thanks darren that worked Just put the VN ecu and harness in and ran power to the anti-theft wire and bingo started up. Cheers for the help.

I'm still abit confused as to why the VR loom and ECU didn't work, i thought that any VR ECU into another VR would just work or are they linked to the BCM which came with that car?

[EQUIPE-T]

Hey thanks darren that worked Just put the VN ecu and harness in and ran power to the anti-theft wire and bingo started up. Cheers for the help.

I'm still abit confused as to why the VR loom and ECU didn't work, i thought that any VR ECU into another VR would just work or are they linked to the BCM which came with that car?

aparently they did a few tests on the VR ecu's and bcm's in readiness for the VS, not uncommon to find a twin pair of VR's ( say a pair of executives ) and they have different BCM's or different ECU's ( very minor difference but enough to disrupt things )

[John]

Power getting to the injectors?

They pulse the negative circuit.

[Darren]

Hey thanks darren that worked Just put the VN ecu and harness in and ran power to the anti-theft wire and bingo started up. Cheers for the help.

I'm still abit confused as to why the VR loom and ECU didn't work, i thought that any VR ECU into another VR would just work or are they linked to the BCM which came with that car?

glad to help
it's been a while since I worked with VR's, but from memory the memcal/PROM and BCM are matched. The BCM transmits serial data to the memcal, and if it matches the code stored in the memcal, it will disable the anti-theft.

if you really wanted to retain the VR ECU (VR ECU has a higher baud rate and more larger calibration file) you could get someone who has the gear to calibrate another memcal with the VATS (vehicle anti-theft system) disabled, and mask the auto DTC's so you could run the VN auto without codes popping up.

[V8 Calais]

Thanks, nah we are just leaving the VN ecu in there cause it works fine and is doing what its meant too. Only thing I will have to do some research into is wiring up the speedometer and then getting the appropriate speedo adjusting unit to allow it to work. Everything else works fine.