"I was wanting to look into running a propane kit on my truck...anyone run this on a 12 valve? what type of hp and tq gains would I be looking at?? I haven't looked into any kits yet, but does anyone know if they are controlled from onboard...or some mount on the dash that will control the amount of pressure of propane coming out? Is there any type of gauge to possible watch the pressure?? Any ideas of the best kit out there? "
Systems are different, so do some homework. Propane gets a bad rap, but if you do a search of this or other forums, you will not find too much justification or documentation for it. Those that have it and use it are usually very happy with it.
You will see gains of around 60-80 hp and around 150 ft lbs torque on a stock or slightly modified 12 valve.
Some are just basically power on and power off, controlled by a pressure switch, that kicks in the engine mounted regulator/vaporzier at a certain pressure that you set. This kick in time can be adjusted, but the amount of propane is kind of set. Some have computer controls that have different perimeters you can set to try and control the flow. Others are variable flow, and controlled and metered with boost pressure, so the flow is throttle controlled and on demand. With this type, your boost gauge is your monitor for knowing the amount of pressure of propane coming out.
