[Vwdiesel] Diesel working on liquid propane

[Roger Brown]

On 10/12/2010 2:09 PM, Tad wrote:
>> From what I recall reading on the TDIClub forums several years back, propane
> on a diesel tends to have a similar effect as nitrous oxide on a gasser.
>   Obviously not the same in that there's no O2 in propane, but it tends to
> accelerate the progress of the slow-burning diesel flame front, increasing
> efficiency in the process.

I think the main thing is that it is a cleaner burning fuel than diesel.  W/ diesel only, 
you can never really get to the stoich. air/fuel ratio as the burning diesel will start to 
make too much soot (like heavy black smoke).  So the idea is adding a small amount of 
cleaner burning fuel to the intake to take advantage of that excess oxygen you have gone 
to the trouble of sucking into the engine and compressing to make a little extra power 
with.  The trick is to keep the propane percentage well below the flammability limit which 
is about 10% (10:1 air/fuel ratio) to keep it from detonating during the compression stroke.

-- 

   Roger