Re: LPG vs Intercooler
Turbocharged cars typically run slightly richer than NA cars and also a lot less advance, the problem with gas is the richer you run the hotter the combustion chamber gets, also the less advance you have the hotter the combustion chamber gets, water injection works excellent on gas, but is a pain having to refill all the time, and if you run out you will destroy your motor in less than a second.
The gas entering an engine is at coolant temperature as it goes through the converter and gets heated, it doesn't provide any cooling effect.
LPGas liquid injection is available, but GRA don't do it. There is a company in WA that makes them, but i don't know there name, sorry.
Intercooling on gas turbo cars is a must, because as the temperature of gas increases its octane rating drops significantly.
I have a turbocharged EA that i have been running straight gas, non intercooled, and no water injection, i had lowered the compression to 7 to 1, fully mapped XE Dizzy to suit and been dyno tuned. I have stuffed two motors now. Why because i never intercooled, and also that you need 30% better spark for gas, you need even better spark for turbocharging and i have found it near impossible to stop it cross firing, and to keep up good spark to plugs.
Speak to GRA, they have done many turbo setups.
I personally am going back to petrol, much safer on your engine.