Outer Limits 4x4 Board

Hi all, i am about to swap the lpg sytem from 81 RR to 85 RR and would like some suggestions on which petrol sytem to use. This is what i have to use - twin lpg tanks (under floor), twin sill tanks, standard strombergs with the lpg adapters and converter to match, 450 holley/ manifold and sprintgas new gen mixer and converter to suit, 86 efi setup ( megasquirt ecu) and impco miver/converter to suit, also have 350 holley /manifold from other RR to use if needed. Basically the easiest will be leaving the original twin carbs and fitting the adapters and the hardest (maybe) is fitting efi as with the sill tanks it will be hard to get the right fuel pressure without fitting a surge tank and complicated fuel line arrangement.
Comments on each from those who have that setup would be appreciated.

thanks,
Nick.

EFI, Mega squirt, fit surge tank, not that hard.

this is not the easiest, but you will get the best performence.

And I think M/S can be set up with 2 ignition curves best of both worlds.

Michael.

HSV Rangie wrote:EFI, Mega squirt, fit surge tank, not that hard.

this is not the easiest, but you will get the best performence.

And I think M/S can be set up with 2 ignition curves best of both worlds.

Michael.

^ What he said, I have 3.9 EFI on gas and will build a megasquirt next year with two maps

I should really order it now, that would motivate me

Tom

Having an EFI only affects running on petrol, it does nothing for gas. Most people that have gas use petrol very rarely, therefore it might be worth the effort to connvert to EFI. I run a new gen mixer and convertor and find them very good. The only issue is that you will never be able to fit a snorkel to it. I run a 500 holley, so the 450 sounds alright. However, once you get into the real hard stuff, forget running petrol through the Holley. On step drop offs or climbs, the carby will either flood or starve. Most other 4WDing they are fine on. So if you are going away somewhere where you can't get gas, save the gas for the harder parts and run on petrol in the easier ones.

The Impco 300a mixer used to have the option of a wrap arround plastic box with a large tube coming off for a cold air intake.
It would not be too hard to fabricate an equivilent item but out of steel for air tightness and pipe it to a snorkle which doesn't have the Ram Air effect
as this upsets Lpg tune with head winds etc.
I feel there would be a performance increase with the EFI manifolds on gas over the old CDs.
J Top

Thanks for the input guys, my ideal setup is the efi but i dont have ecu yet and i am looking to fit the gas setup probably the first weekend after new year. I could just fit everything and run straight gas till i get the ecu and surge tank fitted, i will be fitting a snorkel but not using a ram - may be a donaldson pre cleaner or i may fabricate my own. One other issue i have is my sill tanks dont have sender units in them so what year rangies have senders that are fitted in the top of the tank as apposed to the earlier side fitted ones? Top fitting will be easy to mod the tanks and seal.