'808' tune for ecotec on gas

[rob keith]

hi all.

i am putting an ecotec into my lux but wish to retain 808 ecu (have rebuilt th700 in umit) as an easier mtor replacement, i understand all the hardware differences and am ok with this.

problem is getting a good tune for the 808 ecu to cope with both petrol and lpg.

question is the 12P tune suitabe for gas as well??

regds

[VL400]

The 12P program is suitable for LPG, it has dual spark maps. How you tune it is up to you though, the ecotec 12P cal file by holden202 is not setup for LPG on the second spark map so you would need to tune it for LPG.

[rob keith]

thanx.

still need help for the tune though, have no facilities myself

regards

[The1]

Are you wanting realtime tuning or just burn a memcal for each update?

For Realtime you will need a logging adaptor for your laptop and a NVRAM to replace the standard memcal, both are in For Sale Section.

For Burning to the stock memcal, grab a GQ-4X burner off ebay is the best, the grab a memcal adaptor in the For Sale Section.

Some Reading depending on how far advanced you are.
https://pcmhacking.net/forums/viewtopic.php?f=7&t=1396

[rob keith]

learning as i go here

if i am correct in my thinking the 808 memcal can have two different turns burned to it ie one for regular petrol and possibly the other for lpg and use external switch to select which tune for which fuel

hoping to be able to buy a preburned memcal to just dop in

regards

rob

[The1]

808 and ecotec LPG/Petrol drop in tune doesn't exist, if you had say a VT PCM then you could use a VT Factory LPG tune and with a switch trigger LPG/Petrol modes as far as im aware. But if you wish to retain the 808 then tuning will be required, 12p code as above can do the same thing.

[Holden202T]

if you use 808 and $12P tune then you would need to have some way to cut the injectors when you switch tunes .... i guess it could be done with a relay on the injectors but it would be a trail blazing exercise thats for sure.

[rob keith]

hi
im guessing that already happens when i switch from petrol to lpg??

my fuel selector switch is a 3 position 'pet / off / lpg'

rgds

[rob keith]

hi again

any info on the late factory lpg tune BBMM i think?

is this adedicated lpg or dual fuel?

[VL400]

if you use 808 and $12P tune then you would need to have some way to cut the injectors when you switch tunes .... i guess it could be done with a relay on the injectors but it would be a trail blazing exercise thats for sure.

Could prob use the map b rev limit set to a very low or 0 RPM to turn off the injectors or a flex output too if the LPG changeover relay does not do it.

Also an LPG expert would know much better if this is possible, but could maybe also have the map b cranking fuel tables setup to aid cranking in cold weather?