Hi there,

I am thinking of moving overseas and driving my 89 Corvette which is already there. The price of regular is about $10-11/gallon and LPG costs about 60% of that.

I was watching Motorweek on Pbs, where the host covered use of LPG in fleets. LPG (a mix of propane and butane) has a wide infrastructure where I am moving, so you can refuel at most gas stations, availability is similar to availability of diesel in the US.

I was wondering what is the best place for a tank, any preferred brands and experiences. My cas has about 30K miles, and feels pretty tight. I was told LPG is a dry fuel, so I wonder if there are issues with intake valves and such. I think there are a few LPG setups which inject oil with LPG. I want dual fuel operation, where I can switch to gasoline as a backup, and for start up etc. I probably will run gas periodically so that gas does not go stale.

I am thinking of a sequential gas injection system, where liquid propane is directly injected much like the TPI injectors. I think local mechanics converted similar engines, especially SBC fuel injected trucks, Land Rover V8s, etc.

C4ZF6nut

 

propane systems dont work like the multifuel deisel systems do , when you change the delivery system , its 'dedicated' , but there would be no reason to switch back and forth. propane is a stand alone good working system. Have fun finding the parts for a vette, you might be better to convert to a carb. manifold and go from there, unless you have nice deep pockets, of course.

 

It has been a very long time since I have messed with LPG. My dad owned a propane company so all of our trucks had propane conversions done on them.

We put a plate under the carb and ran the propane thru a unit that had heater hoses to it. It was used to convert the liquid propane to a gas and regulate the pressure. As I recall it took some time for this to warm up so we always started on gasoline and then cut over manually. It is probably done much better these days.

An issue I can think of is that LPG tanks have "pop off" or pressure relief valves incase they build up too much pressure. I would think this would mandate an external or separated location for the tank.
Or at the least a hose to vent the gas to the outside.

Tanks are an issue because of their weight. Since the gas is under pressure you have to make them much stronger. Not much choice on size either. Mostly round cylinders.

I will have to plead ignorance on running LPG through an injector system. My gut feel is that it would not work. Might be better suited to an adapter at the throttle body. But not even sure about that.

Not an authority on this and it has been along time since I have worked with it. (all other standard disclaimers apply as well)

 

The sequential (more advanced than stock Multiport batch fired) LPG vapor injection systems with installation, injectors and tank run from $1200-1500, from Atiker and such on the low end to Prins/BRC on the high end. That said, I would like to keep alternate fuel capability if LPG system has some issues. Otherwise, I am considering getting rid of the rear fuel tank and replacing with LPG cylinder tank. Currently, I am thinking of getting rid of the spare and fitting a doughnut tank there.

The brands I am considering include BRC (Chevrolet vehicles (Korean) are fitted from the showroom with this brand), Landirenzo (GM Europe (Opel) uses this), , Prins, Lavato, Tartarini,Zavoli (Italian), Atiker (Turkish). I hear good things about Prins/BRC using Keihin injectors reputedly the best.

I do not know much about the liquid LPG injection systems, I am guessing these will be more common in the future with direct gasoline engines and such.

C4ZF6nut

 

That is a huge undertaking trying to find space for an LPG tank on a Vette!

Anyway, you say propane is 40% cheaper than gas where you're going, is that before or after figuring in the additional propane required to match gas on a per liter bases. I don't know the number but it can be googled, but propane has less energy per liter and requires more to get things done. I think it is in the 20% - 40% range, that is to say, if you use 14 liters per 100km for gas, expect to use about 20 liters of propane to go the same distance. That may leave it costing about the same

Greg

 

Found it, propane is 75% of gas so the $ comparison is that if gas is $2/gallon, than propane has to be $1.50/gallon just to break even, or in your case propane at or over $7.50/gallon will cost more to run that gas at $10/gallon.

Greg

 

This is one of these things which you need to factor in. Like ethanol, LPG (mix of butane and propane) has less energy per volume, but the consumption is only 15-20% more. It is not directly related to the decrease in energy content, it may have to do with the octane of the fuel, the way it burns etc.

Current pricing for LPG is 0,6x unleaded, so when you factor in LPG still costs 0.7x gas. If you look at it from gas cost, it is about 30% cheaper, if you look at from LPG cost, gas costs 50% more. I want to do the conversion since LPG is cheaper in the rest of Europe, and I may want to go for driving vacations. LPG on gas engines is even less expensive than diesel these days.

With the talk about what people will do when gas goes for $5 in the US, I think the situation there is crazy. Corvette does 25mpg EPA, but I can get 28-29 if I really baby it on the highway.



C4ZF6nut

 

I have never checked the spare tire well. Do you think I could have a doughnut tanks fitted there? I can find 11 gallon tanks fitted to compact vehicles. I think C4 spare tire well could fit one?

http://www.tinleytech.co.uk/sizes.html#t

 

Of course you can fit a tank in your spare wheel well. I converted my Jag S-Type with a SGI kit that I bought from Tinleytech with the usual thing of the tank replacing the spare wheel. I'll also be ordering the parts very soon from another supplier to convert my C5 Z.