Jump to content

Legacy 3ltr LPG conversion.

Recommended Posts

isn't it a bi-fuel car?
Sounds like it will be, soon. :)


Subaru Germany says their system (which isn't available for the 3.0L engine) increases driving range between refueling stops to a bladder-bursting 1,000 km (621 miles). When installed by an authorized dealer, Subaru Germany's system will preserve all Subaru warranties.



Link to comment
Share on other sites

Thanks for your interest in this problem. The motor is a rare import in England and there is a lack of information and we are starting the conversion tomorrow and hoping things will fall into place when we get down to it. Thanks again.
What's so rare about a 3.0L engine in England? Subaru UK has been selling Outbacks and Legacys with that engine for years. Actually, there are two significant variants of the 3.0L. The older one, introduced in 2001, is known as the EZ30D and has a single exhaust outlet per head. The new one, introduced with the 2005 models, is known as the EZ30R and has three exhaust outlets per head, variable valve lift and drive-by-wire (DBW), which is also called Electronic Throttle Control (ETC). The wire diagrams provided in the post above describe the EZ30R and probably won't be helpful if you have an EZ30D.


BTW, exactly which model/year/market is your rare engine from?


Subaru in Japan offers a B4 CNG (Compressed Natural Gas) model, but only as a 2.0L. Natural gas is mostly methane. Methane's knock resistance is so good that it's off the scale for both Research Octane Number and Motor Octane Number (124+). Sadly, the B4 CNG engine's compression ratio is only 11.5:1, the same as the 2.0R engine's, and therefore fails to take any advantage from the additional knock resistance provided by CNG.

Link to comment
Share on other sites

Interesting info Jon...

Has any manufacturer ever tried to turbocharge a CNG engine?


I assume that the fuel is still a liquid until it exits the injector, right?

CNG (C=Compressed) is slightly different from LNG (L=Liquid). CNG can be easily produced from LNG by warming. LNG needs to be kept below -117°F. Unlike LNG, LPG (aka, Autogas) can be stored as a liquid by using only pressure. LPG is primarily propane, which has a good anti-knock index (AKI), but not nearly as good a methane.


Both LPG and CNG are usually delivered to the engine as a low-pressure vapor.

Link to comment
Share on other sites


This topic is now archived and is closed to further replies.

  • Create New...

Important Information

Terms of Use