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-   -   operating FD on LPG (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/operating-fd-lpg-313636/)

judgekim Jun 4, 2004 09:50 AM

operating FD on LPG
 
Has anyone ever looked into converting the fuel of the FD to LPG? It is my understanding that it burns cooler and cleaner which sounds lik a positive for the FD.

SomeGuy_sg Jun 4, 2004 12:21 PM

It has been done before , but not in a FD . There is a turbo SA22C downunder running LPG putting down 320hp ... i shit you not my friend...

http://www.autospeed.com.au/A_0406/cms/article.html
http://us1.webpublications.com.au/st.../0406_13mg.jpg

SiKoPaThX Jun 4, 2004 01:51 PM

well someones gotta ask....whats LPG?

DCrosby Jun 4, 2004 02:31 PM

Liquid Petrollium Gas ? (Guess)

CYM TKT Jun 4, 2004 02:43 PM

liquid propane gas i thought. dunno for sure though

judgekim Jun 4, 2004 02:54 PM

LPG is liquid propane gas. It would appear that from the information provided by "Some Guy" that conversion is not such a bad idea. I have seen kits for converting carburator driven cars for sale as low as $90. Is there a daring RX7 enthusiast out there will to try a conversion on the FD? If I had any mechanical ability, I might try it myself.

poss Jun 4, 2004 02:57 PM

Yeah, it's propane. My neighbor converted his old truck to propane. It was pretty neat, but he also worked for the propane company.

Anyway, it might run cooler and cleaner than petrol, but there are also many disadvantages.
-refueling is not as convienient
-you would have to find a place to store a large, heavy cylindrical tank
-it has a lower btu rating, so you would have to use more per unit power output
I'm sure there are more, but that was off the top of my head.

I'm all for propane injection though. :)

aREX4X Jun 4, 2004 03:45 PM

interesting post!

X...

zyounker Jun 4, 2004 03:59 PM

I'll go into this a little..


Most gas powered cars run LPG only in boost.. and it isnt really liquid injection.. it is vapor injection.. so you loose the benifits of the pressure drop.


And you can get up to 118 octane propane.. so if you just inject it with boost and tune around it you can get ~105 octane and a 5 gallon tank lasts ~500 miles. So you can turn up the boost/timming and make some nice numbers.



I am workin on a true liquid injection system That will have tons of benifits over a vapor system, but it is still pretty far away.

BigIslandSevens Jun 4, 2004 04:02 PM

Atkins Rotary has made a fewconverted engines. One is the lawnmower that Tim Allen raced Bob Vila on. I think it was a single rotor propane conversion. Pretty sweet. You can see it in Dan Atkin's Video in the second gen section. I'll look for the link to show you. It is in his supercharger promo movie.

And talk about a stinky rotary !! Pheww!!!!:D

Here is the video. It is just a short shot of the mower. And some fun with a SC'd FC.

https://www.rx7club.com/showthread.p...hreadid=294242

SlingShotRX7 Jun 4, 2004 04:12 PM

Propane fueled cars are nice and all.. may have all
this and that..

BUT GOD forbid if you EVER get into an accident.
Even a minor one..

My Propane filling station, FILLS tanks up to 250 PSI.
If a tank was to r upture and have a LIL spark.

BABOOOOOOOOOOM, game over lights old, fat lady
will have sung...

BigIslandSevens Jun 4, 2004 04:18 PM

^^ And that is different from regular gasoline how? You compress it hard enough and it goes boom too. As well as with spark. Soo if that is the argument than we should just all stop driving our rolling WMD's !!

I've seen a fuel station go up , Man was that the biggest fire work display I ever saw.

SlingShotRX7 Jun 4, 2004 04:28 PM

Oh yea btw.

Propane boils when it contacts Oxygen.

So true liquid injection is almost impossible unless you
can create a vacuum.

SlingShotRX7 Jun 4, 2004 04:29 PM

Oh yea btw.

Propane boils when it contacts Oxygen.

So true liquid injection is almost impossible unless you
can create a vacuum.

DCrosby Jun 4, 2004 05:13 PM

It's also lighter than air, and therefore to take advantage of it's properties, you'd want to inject from the bottom, in theory, but Im fure the rush / pressure from a turbo will drag the propane into teh combustion chamber fast enough for it not to back up into the TB

SlingShotRX7 Jun 5, 2004 09:16 AM

BIG island Seven.

are you asking what the differnce between Gasoline
and propane is?? You can't be that cluelesss..

Obviously if you compress anything enough and punture it and add spark, it will explode.

BUT: Gasoline doesn't need to be compressed to be used.. Propane DOES.. you don't see anyone going around with a plastic propane cans do you? Propane
can only come compressed in a high psi canister
.

Kento Jun 5, 2004 10:38 AM


Originally posted by BigIslandSevens
^^ And that is different from regular gasoline how? You compress it hard enough and it goes boom too. As well as with spark. Soo if that is the argument than we should just all stop driving our rolling WMD's !!

I've seen a fuel station go up , Man was that the biggest fire work display I ever saw.

Your FD's fuel tank isn't pressurized to 150+ psi. LPG is kept in a liquid state by very high pressure; once the pressure drops, it turns to gaseous form very quickly, and creates far more flammable vapor than gasoline (gasoline doesn't ignite in liquid form at ambient pressures-- its vapor is what ignites-- that's why a near-empty gasoline container is much more dangerous than full one) for the same amount of liquid.

You don't see LPG-powered autos or trucks with their fuel tanks hanging around in the back. They're usually recessed within some stout framework to keep them away from foreseeable impacts.

Jedon Jun 5, 2004 11:37 AM

I've been very interested in this and talked to Atkins about the lawnmower at Sevenstock. He said it is a bad idea to run a turbo with propane, he said it was dangerous because the unburn propane could explode or something.

BigIslandSevens Jun 5, 2004 02:09 PM


Originally posted by Kento
Your FD's fuel tank isn't pressurized to 150+ psi. LPG is kept in a liquid state by very high pressure; once the pressure drops, it turns to gaseous form very quickly, and creates far more flammable vapor than gasoline (gasoline doesn't ignite in liquid form at ambient pressures-- its vapor is what ignites-- that's why a near-empty gasoline container is much more dangerous than full one) for the same amount of liquid.

You don't see LPG-powered autos or trucks with their fuel tanks hanging around in the back. They're usually recessed within some stout framework to keep them away from foreseeable impacts.

I understand the vapors of gasoline are the flamable parts,..( I took science class at school too! Thanks for the refresher course though!!:) Hell i've put out a cigarette in a bucket of gas before. you just have to get it in fast enough or the vapors go boom.

As far as the tanks go,.. Get to Las Vegas sometime and pop the trunk of just about ANY cab in that city. They are almost ALL propane powered and the tanks are in the trunk looking like a kegger laid down on it's side.

Being afraid of propane is stupid. If your afraid of fuel blowing up get out of the cars( whatever they are powered with) and start riding you bike!. Propane is far safer than the new and improved hydrogen vhicles. I mean really driving around in a rolling Hindenberg is pretty dumb.

Either form of fuel is just as dangerouse as the next. If a situation occurs that the propane would be ignited, I can almost gauruntee that the regular gasoline is going to blow up just as easily.

If it was THAT dangerous to use ,then why the hell does almost every BBQ in the world use propane? ( i understand the flow of gas to the BBQ is constant So no BBQ tech lesson needed) Obviously you are not a big Hank Hill follower, :D

Not arguing the dangers, just that they are no more risky than regular gasoline.

And the tecnology that goes into making gasoline fuel tanks has changed dramatically in the years. It is not just a tub welded together. They are tested for impact resistance and integrity as the auto industry has paid out their asses for lawsuits regarding pour tanks. ( Chevy trucks come to mind. Yes the tanks were mounted outside the frame rails and then T-boned, But the tank is just as suseptibale to being crushed in the rear of the vehicle as more rear enders happen than T bone accidents.( Just a guess on the #'s there).

I guess it is all up to you and which explosive fuel you want to power your car with. Again if it scares you though, start walking. IMO

And as for Atkins saying to not do it Oh well They just want the market for themselve. ;)

If any of you do any work on turbo diesel trucks then you'll know that propane injection is the equivalent to NOS on the disel engine. I have installed 2 Bullydog terchnology propane injection kits and the engines and trucks are still living. This is not that dangerous. And the propane is in a liquid form in this system as well.
Oh well ,again just my opinion!

Kento Jun 5, 2004 03:03 PM


Originally posted by BigIslandSevens
I understand the vapors of gasoline are the flamable parts,..( I took science class at school too! Thanks for the refresher course though!!:) Hell i've put out a cigarette in a bucket of gas before blah blah blah :rant: ....
Dude, cut back on the meth :) ....nobody said anything about being "afraid of LPG". With the proper safeguards, it's not too hazardous (LPG BBQs have several, and there's plenty of structural components between Vegas cab LPG fuel tanks and the back bumper). I was just stating the differences between LPG and gasoline, since your statement implied that it isn't any different than gasoline to handle and deal with. No need to puff out your chest and crow.... :D

Try putting out your cigarette in a bucket of LPG and see what happens...

Jedon Jun 5, 2004 03:14 PM

Atkins did not say that LPG was dangerous, he said running a TURBO with LPG was dangerous, recomended a supercharger instead (on an FD??).
I'd love to run LPG or CNG with a big single turbo and tons of boost.

jhillyer Jun 5, 2004 03:36 PM


Originally posted by BigIslandSevens
...
If any of you do any work on turbo diesel trucks then you'll know that propane injection is the equivalent to NOS on the disel engine. I have installed 2 Bullydog terchnology propane injection kits and the engines and trucks are still living. This is not that dangerous. And the propane is in a liquid form in this system as well.
Oh well ,again just my opinion!
...
[/B]
Almost. NOS is an oxidant, and injected from liquid cools the intake as it expands. Propane is a fuel, and performs a cooling as it expands. Unlike NOS, propane will compete with diesel for oxidation.

==edit ...
I'm yapping here, looking for someone that has tried diesel injection on the rotary, once intake pressures rise enough to result in a final compression above 15 Bar. Thank you.

salamander Jun 6, 2004 06:09 PM

LPG is technically not propane. It stands for Liquified Petroleum Gas and is a generic name for propane (BBQ's), butane mixtures (BIC Lighters). LPG is a gas at room temps/pressures but liquifies under moderate compression. It is slightly heavier than air and so it sinks when released. It can be used as an auto fuel but it has a lower BTU value than gasoline and a lower octane number (not good for turbos). Usually an engine loses some power when converted to LPG. LPG is a cleaner burning fuel than gasoline and so engines tend to last running LPG.

seanfd3s Jun 7, 2004 12:04 AM

some one should make one for fds and should tell us about it:D

SomeGuy_sg Jun 7, 2004 09:54 AM

Wow...i did not know so many of you guys were interested in this. There are alot of lpg converts in europe. It is more common there ... i was doing some research on it for school here some websites for you guys

http://www.landi.it/eng/index.html
http://www.shardlowautogas.i8.com/index.html


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