Anyone converted a 911 to propane/CNG?

[boyo]

Just one of those curious crazy thoughts. I had a truck back in high school that could switch between gas and propane, and I was wondering if it's been done for a 911.

(Not seriously considering it, just a curious kind of guy...)

Better have some "2.4P" grille badges made up...

-Boyo

[Fishcop]

Good God Man, WHY!

[Glasgow 911SC]

Dont know if its available over there but in the UK you can do a LPG (liquid petroleum gas) conversion which I guess is similar to the propane setup. The car gets the same power & mpg and the pollution is less. The conversion is a couple of thousand ish £'s. The fuel costs way less as well as there is less (or no?) tax added. The tax brake has only been gaurenteed for a few years though which is off putting.

BTW, I pay 82pence per litre at my gas station. Thats about $5.20 per US gallon!

[Teutonics]

It's LPG, not CNG/propane (or a Porsche for that matter), but check the second car/article from the top on this page:

http://www.bmw2002.co.uk/racecars.htm

200+ HP and 185 lb./ft. out of a two-liter SOHC four cylinder..... not bad.

[juanbenae]

curiuosly killed the cat,,, for good reason

[MAS956]

Believe it or not, I had a Datsun B210 that had been converted to run on LPG once upon a time. At $1.50 per gallon of gas vs. $.75 for LPG at the time, it made economic sense.

That thing was heavy though. Had to beef up the rear suspension to support the 26 gallon steel tank. Then there's the fun of driving around with 26 gallons of LPG up your behind. I got rear-ended on the f'way in that thing one Thanksgiving morning - thank gawd for that quarter-inch steel tank. I promptly had the necessary cosmetic bodywork done and gave the car to my sister to drive for a few years!

[boyo]

There are some interesting upsides... Running at 12:1 compression for instance (octane equivalent of 144?)

You need some form of heating to keep the LPG expansion tank from freezing up where the liquid turns to gas. Normally there's a water loop from the car cooling system.

Conversely, when using a turbo- or super-charger, you should use some form of cooling to get better air density and reduce detonation. With the right kind of heat exhanger, both problems solved.

And last, but not least, maybe it could be used as cheap air conditioning!

-Boyo

[Adam]

I would have thought that the combustion temperatures from CNG/LPG would be far too high and damaging to the (sometimes tender) alloys used in 911 engines.

[red-beard]

CNG and LPG burn with _lower_ temps and less radiance than liquid petroleum fuels.....

These fuels would be much better fuels for the enviorment and for our cars than gasoline....

Metering a gas vs a liquid is always a challenge...

James

[Adam]

Oops! I was sure it was hotter... Even still, Petroleum Gasoline has a lubricant built into it, which LPG/CNG cannot deliver. You'd need to protect your valves and valve seats or modify them for LPG.

[red-beard]

Actually, Gasoline has virtually no lubricating properties. Diesel does.

James

[Tinker]

I use to see a bright yellow 935 bodied mid 70's 911 car that ran on LPG. It had some monster turbo motor in it.

I worked at a neighborhood gas station as a poor college student around 1990. The car would drive by occassionally and the owner stopped by for gas with his regular cars. That turbo made all the right noises. Your post brough up that memory. Have not seen that car in a while.

Tinker

[Jdub]

My car smells of brimstone since I converted it to run on the flaming flatus of the devil's hindquarters. Had to trade my soul but He threw in chain tensioners and 9" fuchs...

John