LPG injection- confusion 1

[bre2kar]

G'day all. I am a first time user here, so my questions may be a bit disjointed but will get to the point at the end.

My questions are;
Do lpg injectors exist that inject lpg in liquid form instead of atmo. pressure?

Is there a constant relationship between petroleum and lpg in characteristics?

Is it possible to set an aftermarket computer (Motech etc.) to convert the value of petrol to lpg in a petrol to lpg conversion?
eg. If you take any ordinary multipoint injection car and replace the standard injectors with lpg injectors. Then take the "wires" from the cars computer that go to the injectors and plug them into a new computer that is programmed to "convert" the information into new information for the new injectors. Therefore the cars original computer is thinking it is still doing what it always does. Also the mapping that the big car companies spend millions of dollars on is not going to waste. All the new computer does is convert the "pulse width" ( for lack of better term) for the new injector.
This is just a concept. Or is it not that simple.

Confused...

 

[franzh]

Confused:

Yes (they are different, and DO NOT USE GASOLINE INJECTORS!)
No, they are very different in all properties.
Yes, most quality programmable PCM's allow custom programming, and you will have to do it yourself.
Your last comment is grossly simplified, but yes, sort of.
It is a concept, is currently in production, and yes, it is not that simple.
Franz


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[bre2kar]

Thank you Franz for your reply. You said that the system I am talking about is in production. Could you please forward any info regarding companies that can supply parts/complete systems. Any info would be greatly appreciated.

Thanks.
Karl.

 

[franzh]

Do a websearch for liquid propane fuel injection. There are at least two in the US and more than a dozen in Europe and Australia.

Franz

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[rdd48856]

Franzh I believe that here in Europe there are only two liquid injection systems currently in production.

 

[turbocohen]

um.. there are a couple liquid systems on the market, most stink and are unsafe. A couple work damn well though.
All the parts for lpfi are on the shelf.
Be wary of top fed lpfi without at least 4 bar boost and a ton o cranking voltage tolerant flow rate.

The walbro and other pumps dont cut it at hot restart when hot fuel vapors have to be purged.

So far the only liquid phase system with adequate hot restart comes from vialle and some privateer garages..

I got pictures, dont know how to post them though.. any suggestions franz?

 

[franzh]

Turbo;

I suggested Walbro since they use off the shelf gasoline based fuel pumps which have a reasonably good history (grin!) but I agree, the European systems have a significant head start on Western Hemisphere technology. Vialle is good, Icom is too. Almost all of the Dutch and Italian companies are preparing to market liquid systems, there are significant advantages to vapor, but also some significant hurdles, almost all dealing with heat.

As for your picture, I think if you imbed an HTML <img> link, you can post one in the message. I havent done one yet but see others that have.

Franz

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