I hope you aren't in the states... it's as illegal as running catless here.
Had CNG on an 87 Falcon overseas, lower COST per mile, but less power and lower mileage per tank.
Ours would start on gasoline, and once the engine was warmed up you could switch to CNG for puttering around town or highway... for actually Driving in town gas was better, more power for traffic combat.
You better run the numbers and see if $2000 worth of kit + the cost of annual tank inspections will pay for itself in fuel saved before you would normally sell the car... . For a lot of people it doesn't.
All is not lost, spend $2000 buying a car that gets better gas mileage in city and stop and go. Geo metro (40s), Mr2 mki N/a (mid 30s), etc for your commuting needs, and keep the hundred of pounds out of the trunk of your 5.
Last edited by attack eagle; 07-28-2008 at 05:56 PM.
Thanks for the great advice.
I live ~30 miles from work, and its 95% highway driving...
Did not consider tank inspections.. I'm going to do a bit more research and make some phone calls before committing to this.