engine ran on propane

[markallen]

im am fixing to buy a 350 from a guy who has been running it on gas but when he bought it it had just been pulled from a school bus and it was ran on propane. i know that propane is supposed to be better on the engine because it does not cause carbon buildup but my question is there any negative sides to propane is there anything that i should check out before putting it in my truck?

[texnician01]

I've dealt with many propane tractors and have converted them over to gas, never did anything other than change the carburetor and a tune up. You shouldn't have any issues other than what you would experience with any engine.

[SS Tim]

At one time Chevrolet offered engines that were factory modified to run on proane (LPG). But the final conversion was done by an upfitter post productuion. Not too sure exactly what was changed beyond this list,but it might be worth looking into. Also propane does run about 100-110 octane.

[texnician01]

OH, I forgot to mention that, the compression ratio will be higher if it was a factory deal, some of them were converted after the fact and then they may not have anything special about them. I guess it would require pulling the heads to be sure. I also notice in the above image they mention valve modifications. I don't know what they would change for sure, nor have I ever come across a difference on a tractor. I'd be interested to know what they do from the factory.

[72 K20]

Watching this !! Just bought a propane setup for one of my old trucks.

The setup is for straight propane but I'm thinking I might want to go dual fuel instead.