propane carb

[bhearts]

so propane pretty much rocks. its relatively cheap, it burns nice and clean cause its a gas at atmospheric pressure. it has performance knock resistance. what keeping you b3 turbo guys or bp turbo guys from running some version of a propane carb. guys back in the day used to run stinking huge blowers on carbd motors and they didnt have any fuel corrections or even a wideband o2 to use, and the muscle cars turned out fine. so why cant we convince our engines to run carbys with propane.?

[bhearts]

http://www.youtube.com/watch?v=JSin7DPh4EQ

[Movin]

It is a better fuel but not as easy to use and finding a good shop is hard enough without finding a good propane shop. I plan on building one after i complete some of my other improvements

[BigElCat]

Just get an IPCO system off a small displacement fork lift. Use the bottle system that can be refilled at COOP.

You'd need to lower your compression ratio somehow.

Your mileage probably won't increase, but your driving range could potentially go up. Cost effectiveness depends on the price of propane compared to gasoline.

Farmers with propane trucks used to say mileage was about the same, the only advantage (besides less pollution) was fewer fill ups. But gasoline has gone up in cost since then. Keep in mind the farmers had large bottles on back their trucks.

[Movin]

Just get an IPCO system off a small displacement fork lift. Use the bottle system that can be refilled at COOP.

You'd need to lower your compression ratio somehow.

Your mileage probably won't increase, but your driving range could potentially go up. Cost effectiveness depends on the price of propane compared to gasoline.

Farmers with propane trucks used to say mileage was about the same, the only advantage (besides less pollution) was fewer fill ups. But gasoline has gone up in cost since then. Keep in mind the farmers had large bottles on back their trucks.

Impco is my favorite, Century second. I have the fork lift tank and two other tanks,one off a van and one off a pickup, much larger than a forklift. They can all be teed together much easier than liquid fuels. I have the auto motive kits off those same rigs, one is a impco 425, way too big but it is for my 289 anyway. The impco 350 will work better than the forklift I think.

The compression needs to be raised to around 12 to 1 for 112 octane and lower btu by 10%, that will give more than 10% back.

If turbo; like mentioned above then compression ratio could be lowered but even with the far quicker throttle response of propane a slightly higher compression ratio would give radical throttle..explosive but no ping and longer engine life.

I installed kits for years and intend to do the Festy but other projects on the festy must be finished first!

[Bert]

Breakdown on an equal unit of volume basis; propane only has about 75% the energy of gasoline. Burns cleaner but you're going to need a lot more of it if you want to retain the same level of power.

[Pu241]

J
You'd need to lower your compression ratio somehow.

Propane is much higher octane rating than gasoline so can raise Compression ratio.

Breakdown on an equal unit of volume basis; propane only has about 75% the energy of gasoline. Burns cleaner but you're going to need a lot more of it if you want to retain the same level of power.

Correct on BTU content, but can recoup much of the loss with higher compression from a power stand point, but will use more propane on a volume basis. Based on bheart's previous posts concerning maximum MPG, he may not want the power so much as efficiency and lower cost per mile. Which he may or may not get as propane like all petrochemical fuels, as risen considerably in price in the 5+ years.

[Movin]

The difference is closer to 10%, but the cost is about 50% per cost per mile. Not counting longer oil changes, less wear and better plug life.

[bhearts]

so does anyone have a link for a propane carb. or anyone thats done one on a smaller car like ours. i dont know the single thing about carbies. so anything would help.

[Bert]

The difference is closer to 10%, but the cost is about 50% per cost per mile. Not counting longer oil changes, less wear and better plug life.

From a US gov't website (Dept of Energy?), per unit volume, I have written down: diesel 128.5 Btu, gasoline 117 Btu, propane 85 Btu, ethanol 76.3 Btu and natural gas 75 Btu. This suggests quite a bit more difference than 10%. 85 divided by 117 is 73 %! I do know propane was all the rage (gov't subsidized) in Canada in the early 70s for taxis and fleet vehicles until the drivers came to realize there was a noticeable drop in power.

[lessersivad]

http://www.afdc.energy.gov/pdfs/afv_info.pdf

I agree that raising the compression ratio would be a very good way to help, but the "bang for the buck" when it comes to BTU's is hard to get over.

That said, i have a homebrewed, propane carbed mobile genset that is powered with a 1983 Ford Ranger 2.3 spinning a 15 KW gen head.

Not the most efficient set-up but the fuel never spoils and it can power the whole house and garage.

[BigElCat]

'Rodger that' on increasing the CR, rather than lowering it.

[jawbraeka]

i hope this helps you out

http://www.propanecarbs.com/examples.html

here is another link

http://www.nashfuel.com/conversionkits.asp

[Pu241]

Not the most efficient set-up but the fuel never spoils and it can power the whole house and garage.

The fact it doesn't "go bad" is a huge plus as far as I'm concerned.

[Movin]

From a US gov't website (Dept of Energy?), per unit volume, I have written down: diesel 128.5 Btu, gasoline 117 Btu, propane 85 Btu, ethanol 76.3 Btu and natural gas 75 Btu. This suggests quite a bit more difference than 10%. 85 divided by 117 is 73 %! I do know propane was all the rage (gov't subsidized) in Canada in the early 70s for taxis and fleet vehicles until the drivers came to realize there was a noticeable drop in power.

Agreed from the text book, when taking off a gasoline carb or doing dual fuel I was seeing only about 10% on the dyno. Tuning a propane carb is way more accurate than "factory" calibrations of gasoline carbs.

The really strange part is people were saying they got better mileage on propane but that part I could not validate. My own experience was not much difference, to a little loss compared to EFI.