Propane

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Revision as of 21:38, 5 March 2011

Datsun 1200 can run on propane. Datsun had a factory 510 with propane sold in Japan. Although propane contains less energy (so you will take a hit in power), it burns clean, can take high compression and can be less expensive. There are lots of propane Datsun out there -- any gas engine will run on propane. A mixture of propane and butane used mainly as vehicle fuel is commonly known as liquefied petroleum gas (LPG).

Carburetor

Datsun J15 LPG carburetor

revhead001's L-series Datsun engine IMPCO 125 mixer with a IMPCO J convertor.

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I used an origional nikki base and made an adaptor to fit the mixer. The J convertor is just a 1/2 version of the daddy model. Like a B2. Although it is a basic setup it chews around 18 litres to 100km approx [13 mpg]. Still beats the price of petrol.

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Considerations

Efficiency

Sikyne: used two of those throttle plates, ca125 mixers, twin SU manifold on a L series. It was very difficult to get mixtures lean enough, had to run extra idle mixture shims(fitted in the air valve). This set up even when properly dyno tuned was not as responsive, not as economical and only marginly more top end over a single CA 125 mixer...I also tested a CA 200 mixer but the 125 was better...But gas injection made another 20KW over a CA 125 mixer on my A series..

revhead001: Half the reason that your engine is so hard to tune is that the carbys are too big for the stockish motor to start with...You can't have power and economy with lpg. Trade one for the other. Unless you go turbo.

B210sleeper: I actually have too much carburettor, it's about 60mm with a GA16 throttle body,it needed a restrictor put in the intake to get it more vacuum signal...using omvl equipment, seemed more suited to cars than impco...i've struggled with fuel economy ... 18l 100km is about 15 mpg, thats' about as good as i've ever gotten in the city.i've had 30 mpg+ on the highway. i look at it as lpg is 1/2 the cost of petrol, so i'm getting 30 petrol mpg even at the worst ... 20 petrol mpg city and as good as 60 petrol mpg highway.... creative accounting? not any more than a hybrid...the short answer is a turbo... lpg likes 12.5:1 compression, economy should be much better then, if you can keep your foot out of it. debating just buying the turbo already and getting started...

B210sleeper

B210sleeper's Datsun B310 using a European setup from omvl in italy, it's a variable piston carb.

It gets 13 mpg street and 30 highway on propane, still being tuned...

LPG powered A15

Bottom left: propane vaporizer
Up diagonally: mixture solenoid
Up from that between cone filter: propane mixer
90 deg bend into GA16DE throttle body. 
Blue hose running all over, oil plumbing.

Using Autronic AL-600D lambda (O2) sensor system.

Fuel Injection

There are LPG direct injection kits, which are cool if you have a factory EFI already, or a Megasquirt, it would be fairly easy to change to injection.

As of 2010 in the US is the propane is too dirty for liquid injection. Leaves nasty tar, propylene, and sulfur deposits in the system.

Turbo

Turbo can be intercooled blowthrough, the vaporizer has a boost reference port, so it's easy. The expense is getting a turbo and making up an exhaust manifold or j pipe.

Air/Fuel Ratio

You can run an O2 sensor just like for gasoline powered engines.

Stoichiometric ratio for gasoline is 14.7:1. Propane is 15.7:1. It is more dangerous to run a propane engine rich than lean (more likely to detonate -- the opposite of gasoline.