Anyone running an air-cooled engine on LPG gas fuel. I am thinking of building an engine using this fuel and wondered about other people's experience of using it or anyone's experience of building an engine to run on it.
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I think you're going to hear a lot of crickets on this one.....
Remember that Google is your friend.
tumbleweed... I guess you don't need to bother in the US but in the UK emissions are an issue..
So in most US states (cities), there are emissions exemptions for older cars and their emissions produced. Some say cars over 25 or 30 years old are exempt. Others say they must have the air pollution equipment provided as when new (like air pumps, recirc valves, catalytic converters). In states that is why you would prefer to have your vehicle registered as the year of the chassis vs the final build date. Your 1970 VW pan based car might be exempt or meet 1970 air standards (save for the big P&C, dual carbs, hot cam) BUT if registered as a 2015 build, it would be expected to meet 2015 emission standards. This also becomes an issue with non-VW pan based cars - where they are registered as year built. Many states have Specials Construction titling procedures to handle this.
I see old MG/AH/TR on UK roads - are they exempt or somehow compliant to emissions. Plus diesels are still increasingly popular. LPG generally produces far less power than a gasoline engine - so who'd want to putter around in an 18 hp Speedster? I think one reason for retrofitting a Subaru engine is for emissions (plus less maintenance, longevity, power, reliability, etc.).
What a bummer it was to Prince Harry drive off in an electric E-type Jaguar (left hand drive - to boot!) after his wedding. I'm sure he had better choices - but he probably isn't a car enthusiast.
Well, they should be here, too, but we have this current "Administration", see..........
Personally, I see absolutely no cooling issues using LPG fuel in an aircooled engine. My home emergency generator runs on Natural Gas (a couple more in this neighborhood, too) with no problems, and someone in town runs an airport shuttle business with about 30 vans and ALL of them are running on LPG. I once asked one of the older drivers about performance and he never noticed any difference between the before, with gasoline, and the after with LPG. Several local trucking companies are now running all-LPG tractor trailers, too - it's becoming more popular all the time.
I found a decent thread on conversions here:
I'm sure you can do it, but don't know of anyone who has. I know there are a few V-8 Cobra replicas running LPG.
I converted my gasoline generator to run only LPG. The conversion consisted of plugging holes with RTV and drilling out the main jet so a propane nozzle could be installed in it's place. It wasn't hard. I NEVER have to worry about bad gas or clogged carbs, that's for sure. The engine runs CLEAN, I don't run it much, and don't need to change the oil very often. Generator starts with 2 pulls, every time, for the last 15 years!
Anyway, once you convert and get it running, I'd suggest a wideband to set the full-load mixture. Once you do that, I think you're done. You don't need accelerator pump, as it's a gas mixing with another gas(air). You also don't need to worry about different cylinders getting different mixtures.
I'll bet you could almost use the same setup as my generator. Good luck, you can do it!
Danny wrote: “I NEVER have to worry about bad gas or clogged carbs, that's for sure.”
hmmmmmmm....... Maybe you should sell Drake on this conversion for the Hoopty?
I've seen one LPG powered VW engine on a cable way for gondola cars at one of the larger theme parks... 40hp engine.... Stock as a stove....