I just read the first page of comments on here because I am thinking of adding propane to my non-turbo 7.3 IDI, when I noticed the ongoing debate about how to regulate flow of propane. I know nothing about plumbing propane and regulators, but I do know that in the propane systems the propane is used to help burn the diesel that would otherwise pass through the engine unburned. This information, combined with the fact that at any given RPM the amount of fuel being delivered to the engine can vary depending on load (how far down you hold the load pedal), leads me to beleive that the ammount of propane flow should be based on the amount of diesel being delivered to the engine, and a ratio should be established (x amount of propane for each unit of diesel) for the most power and effeciency. Theres my 2 cents, and as far I can tell theres no feasable way of actually making this happen, or is there?

 

Essentially you are correct - the amount of propane supplied should be proportional to the amount of diesel that is flowing into the engine.

It isn't that there is no feasable way to do this - just that there is no truly simple way to do it....

 

Despite Propane Injection Being Billed As the "Next Best Thing to Sex," and having promoted it for years myself, I have found some caveats to its use in IDI engines.

I spoke with the engineer (who shall remain nameless) that designed one of the systems on the market now and, after testing, they made a point NOT to offer a kit for IDI engines, or recommend them. I found the site below that explains rather well how propane injection works and also why it's not so hot for IDI engines... especially NA IDI. Saves me a lot of typing!

In a nutshell, IDI engines do not mix the air, fuel and propane as well as a DI engine, so hot spots and pockets of pure propane can be the result.
According to what I was told, if you are going to use propane in an IDI, set it up to kick in only at high rpm/high boost so that the propane has the best chance to mix well in the combustion chamber. Using propane for low rpm lugging (in an IDI) can be the kiss of death. Anyway, my conversations have changed my mind about propane on my truck, irrespective of what "everyone" says. Years ago, I wondered why Banks was so negative on propane, thinking they were against it mostly because they didn't have a system. Now, I've gone back and reread their tech stuff on it on the Banks Website and it makes more sense. For DI engines, I'd still consider it but since I'm happily "stuck" with an IDI engine... !

If raw power is the goal, the better choice is a little nitrous, which is an oxidizer only and allows your engine to use up some of that black smoke rather than spew it out the back. Yeah, you do have to be carefull about amounts, but the same is true for propane.

Propane Fumigation

BTW, I'm not going to argue this point with anyone. Make up you own mind. I've given you a couple of online sources and you can find more. Just remember to seperate DI and IDI engine in your mind whatever you read. Most of the good dtuff you read concerns DI engines.

 

Hey Guys,

this is off the topic a bit but I know a guy that is interested in installing a new propane injection system that has heretofore not been mentioned. hmm...but anyways, he wants something like a 20-30 gal tank. Would or could anyone recommend a spot where this beast could be attached?

Thanks,

bbiofuels

 

The only place to mount it in an Excursion would be a frame mount Manchester Tank.

http://www.mantank.com/products/rv/rvcylinders.htm

The picture all the way at the bottom of the page is the correct tank.
30# is the biggest size though.

Last time I priced one it was over 500 dollars as I remember.