The V8 Owners Forum -

hi guys

i have a discovery 1 (92) with a 3.5efi lump fitted, it has hot wire injection and is non serps.

i intend this summer to convert to gas for economical and environmental reasons.

now ive seen a number of kits that have a mecanical by vacuum mixer/vapouriser arrangement that uses emulators to fool the efi system into thinking its running the engine. also seen full sequential lpg gas systems to that are very expensive.

my question to you guys is.

is it worth having the efi system fitted when running a mechanical lpg system or would it be easier to have a set of carbs on standby for the odd occasion i run out of gas or cant get some for another reason, im not a fan of all the sensors air flow meter ecu gubbins thats all nearly 17 years old and dont really trust it to work when i need it. (its not running marvellous on petrol now)

ive read threads about various kits being reliable so if any one has a supplier in mind to get a full kit to fit i would be extremly grateful, ive seen the omvl vapouriser at rpi engineering on ebat that has been mentioned.

if any one has any suggestions for a good install from a very beggining point i would be even more grateful

im more than competant with the spanners so will be hands on doing it myself.

cheers for reading look forward to a reply.

merry christmas by the way to.

If your petrol injection system is Hotwire it should be OK, for LPG.

I have convereted my own 3.9RRC to a sequntial LPG system(and certificted), supplied through www.tinleytech.co.uk. there are other suppliers also.

You will need to decide what sort of system you want, either vapour induction or sequential injection(most modern systems are these) the latter are less prone to back firing, assuming the set up is OK.

You will also need to decide how big a tank you want and where yo're going to put it!

You don't need the emulators necessarily, I don't have them modded the harness to remove power to the petrol injectors when on LPG.

I'm sure others will also add their comments

hi thanks for the reply, im basically unsure of whether to have sequential or induction kit i havent any experience of either at the moment, im hoping to develope some idea of the ups and downs of both systems through this forum.

my biggest fear is of relying on so many electronic devices on the efi system air flow meters temp senors ecu etc etc, that if any thing lets me down it will cost an arm and a leg to put right.

wheras having carbs and an induction lpg kit is less complicated and less likely to give any trouble over time, with the obvious loss of some power and economy how much im not sure.

i have a manifold and some zenith carbs i could fit though would probably seek out some su`s to fit.

if any one can convince me the sequential kit is better by far im willing to listen and learn.

ive heard a lot about blow back i asked rpi about this with there kit and they said there twin setting power amplifier which has preset timing for petrol and another for lpg and with a set of good plugs and high performance ht leads vitually eliminates the chance of a blow back.

is this true ?????

cheers again guys

Heard a few people shot down the RPi dual timing amp, but can't comment personally, I just advanced mine manually and have a spanner in case of LPG breakdown

Sequential is better, only input I have off the Petrol EFi which can wear is the throttle pot, although there are other connections .

got to go now but will give additional info another day