I am setting up propane injection on my 4cyl truck and would like to know the experience of others in comparison. All my hoses are 1/4 hydraulic with 1/8 orifice fittings run through a solenoid that has a switch on the throttle linkage set to open at 3/4 full throttle. Additionally the tank has a regulator limited to 1/2 psi. LPG is right now disconnected while I evaluate the benefits and likely add a toggle switch to manually turn off/on the LPG injection.

I have run this setup and it seems to be just right, a very slight increase in power but no overrevving and only a slight raising of rpm at idle. No pyro increase, in fact due to the lessening of general fuel use it sometimes lowers the pyro.

My driving conditions daily are very demanding, at least 1/2 mile of 18% grade always and often with a load. The extra power is a real help because I like to run oversize tires and heavy rims to deal with bad roads.

But clearly there is extra stress on an engine with propane injection. The question is how much stress is due to just the addition of any LPG - as I think the amount is OK - and is it worth the trade off in my case.