james34cameron

Unless it's changed recently, Victoria was the only state using straight propane no matter where you bought from.

i think one of the things about 100% propane is it burns hotter? could = other issues i guess.
there is a local gas supply here that sells it at the pump for same price as the servos sell the mix (was never conveniently open when i was due to fill up. 
 
My high compression XF would ping on gas but wouldn't ping on 98 petrol and that was with the dizzy advance locked(dyno guy reckoned that suited the LPG best on engines like mine? it was a strong engine, chopped My mates tickford VCT 4.0 fairlane )

I don't think many have gone to the trouble of modding an LPG Barra. Same principle applies to them as with a petrol or diesel.... More air and fuel in, more bang, bigger torques. Spin it harder and more horsepowers. It's not easy when this engine is pretty much maxed out already and being a long-stroke design, is hard to get it to rev more than it does.

Of course, the usual exhaust mods might wake it up a bit, but with LPG you are also dealing with a fuel that takes up more space in the inlet tract than just plain air so there is only so much fuel/air you can get in.

Maybe look at camshafts and what mods they do on NA Barras. I'd say again, not many bother with an NA tune when turbos are so easy to build now and proven to gain so much more, as in dollar per hp.

Ford had already hot-rodded it as much as they could, so there's little headroom to improve. Really the only next step is to put it in something lighter.

Sent from my CPH1903 using Tapatalk

I am not sure on this, so others in the know may shoot me down.
That said, I have a little LPG knowledge.
I have experience with gas, but not in a forced induction situation. ( Impco systems mostly)
My thoughts would be to convert from the complex converter/simple mixer system fitted factory, and change to a simple converter/complex mixer system.
A B2 converter and Gasresearch mixer is a known quantity with blow through LPG systems.
It can be made work very well.
Other people have had great results with Impco mixer and converter systems with forced induction.
 
I have not done either, but I know a lot of people have with great results.
 
 

is it injected gas? watch this series if so
 
 

I think part of the issue is the LPG itself.  Years gone by, it was great, with an octane rating around 100. But over the years (I believe) they have watered down the mix. 50/50 Propane Butane, but now it's more like straight BBQ gas.  Many older builds (clevo's etc) started pinging, as their compression was too high. At least with Petrol you can add a booster or switch to Premium.
 
May be wrong... 
 
Usually am.
 
Drink a lot.