Originally Posted by BrianW
Can you convert to a dual-fuel system? My friend has a 2012 E350 that CNG and regular gas, with a switch to go back and forth between the two systems.
A dual-fuel system has two sets of injectors and associated wiring. I've looked at them and a conversion from my CNG-only setup would require ripping out what I've got to replace with new. I'd be required to change out my tanks, because installers won't warranty used tanks. I've been unable to find a junkyard that'd let me salvage a hybrid system to put in with my existing tanks. So, we're talking about a whole new system, which isn't worth the money.
I'll just use a dual-van system; using the gasoline van when that's appropriate and the extended range CNG van when I can instead. The CNG tanks have a life limit, at which time they must be replaced (nobody wants a 3600 psi CNG explosion). So, the second CNG van will also eventually be converted back to gasoline as well.
.... or, I've got a couple of 86 kW (110 HP each, for a total of 220 HP in a 4WD system) Bosch motors, controllers, and DC/DC converters that could also go in, although I'd need a trailer to carry all the batteries it'd require.