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i remember a few years ago one guy telling me how he was running a old gas setup through his turbo car, i think it was a corolla?? he said the car backfired and the intercooler made one massive big explosion tank which went bang in a big way.

another friend of mine had a VL turbo on gas, and he would explode his air box and destroy AFM's, i remember once it happened it scared the crap out of me.

Be interesting to see how these direct injection setup's go.

I dont get it, why? A little bit more power at the cost of long term damage that might reduce the life of ur engine? Filling up every 100km and waiting 10 mins for it to fill? Wont it run extremely hotter than on fuel as gas is dryer? I could be wrong but yea lol

lp gas is 104 octane, cheap and avail everywhere....

if i had a turbo daily, say a chaser for example with just a highflow, i'd do it fer sure as i could get away with 6 injectors, and pick up a fair whack of power safely

but e85 is better for my current application (300+rwkw on lpg = 12 injectors and a lot of f**king around for only 104ron)

Yep I did :down:

Just wasn't interested in arguing how much it costs, how it's not going to work, and how everyone who's never done it before seems to know how to do it the right way :whistling:

On a side note though, for everyone chasing 120 hp per cylinder etc, I have a big question? Why? Not why is everyone chasing big horsepower, that's a given, but why does this high horsepower have to be on lpg. 99% of driving where fuel economy is concerned is going to be done sub 250hp (probably sub 200hp) and any system these days can be easily switched been fuel and lpg and good systems like mine can switch at a given rpm (I cut over to normal fuel at 6000) under normal conditions, so why not keep the big fuel system for the 6000 rpm launches with 30psi of boost, and just run the lpg the other 99% of the time?

I seen them do this to a hotrod and got arround 650hp out of a chevy 350. They said that injecting propane as a liquid just by the injection process will make 5-8 pounds of boost in the intake. Plus the octane rating is so high that it's basicly like your running race fuel but at half the cost of shitty regular. I was thinkin of building my Dodge up for propane and getting a stroker 390 11.5/1 comp built to utilize it. The only problem i found is that it's a pain to put the tank somewhere.

A few pics of tank and filler.

I went with a small tank which fits between the wheel arches so as not to lose and usable boot space. You can see from the pic that it's not obtrusive. It's a small tank, but suits for the moment. Later on I'll change the fuel tank to a smaller one and pony up a second bottle underneath.

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Hey there this thread is interesting but as the previous people discussed Liqiud injection can be used in high hp applications with either the use of twin injectors or the new improved high flow liqiud injectors,

We have converted a few Xr6 turbos with this system and its fantastic and with a decent tune can produce in excess of 300 kw at the wheels and more, with extra injectors can go beyond this, liqiud cannot backfire as its the same principles as a petrol fuel system, just under higher pressures.

we can currently fit kits to any pre-2004 vehicles with custom setups available,

the only down side of a liqiud conversion is the cost,

in excess of 5k for a custom setup/tune but the results are amazing

my 2c worth

cheers john

What people got to remember is that octane rating is a measure of resistance to detonation or pre ignition, not the stored potential of untapped HP. The higher the octane , the slower the burn. Duel fuel cars are always slugs on gas cause there set up to run on petrol also which requires generally around 10 degrees before top dead center ignition timing at idle where as LPG needs around 20 degrees BTDC. You retard a petrol engine 10 degrees and tell me how it feels. Now bump that compression up around 13:1(for atmo), get your fuel delivery right and set your ignition to suit with a good strong spark and I garantee you will have some kick in the pants. Dedicated is the only way to go with LPG vapourised systems.

I'm not sure how far the factory ECU's will advance the ignition with factory maps and running piggy back injection systems but if you can get an aftermarket ECU with duel settings of timing and injection to suit each fuel at the flick of a switch, that's where you'll get the best out of both.

The biggest problem I found with turbo LPG is definately finding someone who really knows their stuff or even wants to. I ran around in a turbo Hiace for a few years and had a ball. Good luck to all those having a go with this. Alternative fuel research is something we all have to grab by the balls if we don't want to go back to horse and cart some time soon.

What people got to remember is that octane rating is a measure of resistance to detonation or pre ignition, not the stored potential of untapped HP. The higher the octane , the slower the burn. Duel fuel cars are always slugs on gas cause there set up to run on petrol also which requires generally around 10 degrees before top dead center ignition timing at idle where as LPG needs around 20 degrees BTDC. You retard a petrol engine 10 degrees and tell me how it feels. Now bump that compression up around 13:1(for atmo), get your fuel delivery right and set your ignition to suit with a good strong spark and I garantee you will have some kick in the pants. Dedicated is the only way to go with LPG vapourised systems.

I'm not sure how far the factory ECU's will advance the ignition with factory maps and running piggy back injection systems but if you can get an aftermarket ECU with duel settings of timing and injection to suit each fuel at the flick of a switch, that's where you'll get the best out of both.

The biggest problem I found with turbo LPG is definately finding someone who really knows their stuff or even wants to. I ran around in a turbo Hiace for a few years and had a ball. Good luck to all those having a go with this. Alternative fuel research is something we all have to grab by the balls if we don't want to go back to horse and cart some time soon.

What epigram says is dead right about the timing and I don't know of any lpg ecus that do anything about changing timing.

There are a couple of options however with an rb series engine. You can tune for lpg only if you run with LPG dedicated and then run the petrol only for startup and engine warming. Or run it as automatic duel fuel so that it runs petrol for startup and warming and cuts over from lpg to petrol at a certain rpm. Engine maps are a cross of Throttle position and rpm, so you can adjust timing accordinglyfor when it will be on LPG and when on petrol.

The best option though would be to use the RB knock map and tie in a switch to the knock sensor to have it flip to the knock map. This way you can have 2 timing maps, one for fuel and one for lpg. The only downside is that I don't know of any way to switch it back to the default map without resetting the ecu by turning the car on and off. Chances are there is a way.

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