Old Technology not applicable!
I will address JR comments as insets:
This is a bit more on Blue's post a few days ago re: the 1977 article on propane/diesel conversion of Datsun L-4 and L-6 engines. First an observation, then a question (or two).
My father had our 65 Mustang (289) converted to straight propane (not hybrid gas/propane) about 25 years ago. The drawbacks were
1. That the gas tank was removed and this giant round tank was placed in the rear of the car, effectively taking up the whole trunk for anything bigger than a lug wrench.
>>>> I was discussing a dual-fuel option where a smaller 5 gallon "fuel cell" style BBQ tank sized tank was used for track usage---providing CHEAP 110 octane fuel.
2. The car did not have the same power as it did with gas. Decent, but not as much.
>>>>OLD TECHNOLOGY. The vast majority of IMPCO conversion s did loose power because of several factors:
a) the compression was not optimized for the higher ocatne. Purpose-built CNG and LPG engines OUT TORQUE and OUT HP theri gasoline counterparts. This was for a turbocharged conversion, so "less power" would not be a problem---it will take more fuel and more boost, and more timing than gasoline, so it will make more power in this application.
b) timing could not be changed for LPG operation, loosing power
c) old style gasseous carburetors were horrendous at metering proper fuel to compensate for some tings, and as such were set to run "safe rich" compounding the power delivery issue.
3. Propane is not that easy to find on the road, and a year or so after the conversion the "cheap" aspect went away. It was then more per gallon (probably $1 as opposed to 90 cents for gas).
>>>>That has since changed! Almost EVERYWHERE has it now, and there are even dedicated LPG VEhicle fueling stations now. Though it is still cheaper to buy it from a U-Houl or bulk distributor. Actually, the more remote you are, the greater chances you have that a bulk distributor will be in town for residential usage, and you can fuel there. Again, though, only a problem if it is not a dual-fuel vehicle, which is what we are talking about. Right now, propane is anywhere from $1.50 to 1.79 per gallon, for 110 cotane fuel, whereas 104 octane gasoline is around $5 and up...
For run of the mill stuff, costs are close, with LPG still about 30% cheaper than petrol, but it's only aboue 25-30% of the TOTAL cost for equivalent racing petrol!
The 'Pros' were
1. The engine ran incredibly clean. Literally, we never saw dirty oil after that. Although we still did change oil occasionally (because it seemed like we should), the engine was spotless inside.
>>>This has not changed.
2. No warm up. Start the car and it was ready to go.
>>>This is not exactly so. YOu must have been in a place that was WARM. On northern climes it was possible that it would be cold enough that the propane would stay liquid in the tank, and not gassify at all! This is why dual-fuel is the better way to go. If it's -45, you ain't getting an LPG car started unless you got dual-fuel! It will not gassify in that temperature!
3. Little to no discernable wear. This goes back to the cleanliness, I'm sure. Sold the car to a cousin, who drove it, then his daughter drove it. He told me recently that it was sold to some group of Ford guys who restored the body of the car, but kept the propane and it's STILL going, umpteen hundred thousand miles later.
>>>Again, still the same!
4. With all that weight (of the tank) in the rear, this car was killer in snow.
>>>Again, with only a five gallon "cell" this would not be an advantage, disadvantage in the particular application we were discussing.
There is a difference between using it for daily driving, and using it as a "fuel cell" addition for racing use only. It becomes very easy now with current fuel injection technology, and for a TURBO car with "variable compression" you get a killer duel-fuel vehicle with MORE power on LPG than on Petrol!