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Hi,

I'm thinking of converting a VP V6 to carby, but still want to keep DFI coils and be able to adjust timing via real time ECU.
Can it do spark only control and how would rev limit function work? As there would be no fuel cut.

Thanks in advance

spark only is perfectly doable, and I did this on a 202 with carby but you wont have rev limiter unless you use something like VL400's coil driver module and use LSx coils.

there will be no rev limiter 808 cannot do spark cut...
just remove injectors and leave the rest alone. put a tps on the end of the harness and hide it somewhere... tps doesnt need to be on the throttle shaft, it just needs to be plugged into the loom, or else your spark advance will be locked. then the 808 will have spark control only. I did this once on a carby 304. ran so much better with a computer controlled spark map.


if you use a VR auto pcm (you can use this without an 4L60E, just leave trans harness disconnected and disable the DTCs for it) and use $11P code, then there is a spark cut option for rev limit

Ok, thanks for the info.

Thinking out of the box, can I use a tacho shift light to control relay for ignition and thus rev limit?

not ideal. removing power from a coil will cause it to fire. perhaps even prematurely as you could be removing power at any time in the engine cycle. while it would work, it may cause long term engine damage.

Thanks guys