Has it been done? If not, why not?

Just reading up on LPG now and it sounds quite interesting

Hmm, wonder if it's worth cross-posting to the Scottish regional forum ;) :D

[Edited by jlanng - 9/16/2002 11:28:13 PM]

Seen a classic shape WRX for sale with LPG conversion in a local paper (South Wales) about 1 year ago, dont know anything about it though sorry, just that it has been done.

Turkish 1

I was tootling around in a merc before the STi and I ordered LPG, when I got the STi I looked at putting the LPG onto the scoob instead. The answers I got were...
1. Yes we put some extra injectors on the system to cope with the power and it runs spot on. Have done a standard WRX.
2. Wouldn't do this ever, the power output causes huge problems to the burning of the LPG and hence power fluctuations. Seen 3 cars converted and none of them good.
3. If your cars new, forget it cos your warranty is void, it effects too many working parts of the car.

All these responses were from registered convertors, I think you can safely say that it really is a suck it and see exercise. Suffice to say I didn't go through with it as the warranty was the only reason I bought new UK.

p.s. Did convert an Alfa Spider 3.0 - FANTASTIC, cheap and reliable, but a shame the car was not too reliable (not due to the LPG)

Cant see the point in upsetting the performance of a turbo engine by asking it to suck a golf ball through a garden hose! I thought the idea of a turbo engine was for its performance Not economy, if you want economy, buy a diesel for weekday travel,save the scooby its its proper format for the weekend.
Converting a turbo engine will cause so many "knock on" effects, its not viable and would only demand you take it all back off again,or no one would want to buy it with it fitted, once they'd driven it.
better still, only have it fitted, once some company can let you drive a demo turbo with one fitted, you'll see then for yourself how poor the power will be.

Ive got a video of the mitsubishi lancer story and on it there is an evo 4 i think with LPG conversion, he claims it dont effect the performance!

who knows

Advantages of LPG:

cheap due to low taxation
Higher octane rating (around 105) therefore possible to run higher boost or compression or more advanced ignition etc.

Disadvantages:

Lower calorific value than petrol so less power for a given amount, you need to burn more to make the same power

Overall:

If time was taken to get a conversion right, it would be just as quick as a petrol only model but would be less economical (still cheaper to run though).

Personally, I'd want a fully progammable ECU to alter fuelling, boost and ignition timing.

You would probably not get your money back on the conversion unless your mileage was very high. IMHO, I wouldn't have thought it was worth the trouble.

LPG is fairly neutral compared to gasoline (petrol).

By and large LPG is physically and chemically similar to gasoline. For instance the AFR's and the flame speeds are similar. As already pointed out by NotoriusREV the octane rating is higher which helps.

However the calorific value is lower BUT LPG for manifold injection, port injection or early-phase direct injection LPG does produce significantly higher charge cooling (just like an intercooler but better), therefore the mass of fuel and air delivered into the cylinder is increased. Thus the bad effect is largely cancelled out.

Just a thought, as this topic has come up again......

Is it poss to have a system that mixes LPG and Petrol say 50/50?

There is an Alternative fuels show at Gaydon today and tomorrow and Subaru are one of the listed manufacturers. Might be going.
www.drive2002.co.uk

PS

One of my colleagues has converted an Sti Wagon and he claims it runs just fine.