Propane Motor Fuel Injection

[LotusM50 at aol.com]

Hi-

Speaking of CNG and propane systems, could anyone give me a quick rundown on
what is involved with a CNG injection (or carburetor) system in a car
compared with a gasoline system?  I would also be interested in any energy
efficency and economic issues invovled with CNG relative to gasoline.

Would a CNG system designed from a clean sheet of paper be different than a
CNG conversion system?  What advantages would there be?

Thanks,

-Bonn Macy