Propane/water/alcohol injection and O2 sensors

[Perry Harrington]

I think that you all are being mixed up.  There is one fundamental that
you cannot escape:  Propane is 95,000 BTU per gallon, Gasoline is something
like 114,000.

Propane will always provide less thermal energy than Gasoline.

Any gain in HP is entirely due to phase, temperature, and residual efficiencies
of atomization.

Propane has less energy than Gasoline.

All the commercial Propane injection I've seen puts the injector in the intake
elbow of the air path, shortly after the air cleaner.

I had a friend with a Propane powered Caballero, he said it was less powerful
than when it ran on Gas.

It makes sense that liquid Propane would make more power than gas, because of
the density of the liquid and the neccessary state change to a gas in the combustion
chamber.  Instead of losing all that thermal efficiency in the intake, where it
makes a low efficiency cooler, you get it directly inside the combustion chamber.

But cooling the intake charge extremely is counterproductive to combustion, and so
is the higher octane of Propane.  Unless you need the extra octane, you'll get less power.

So, to sum up:  Propane has less energy per lb than Gasoline.  It has a higher RON
than pump Gasoline.  Therefore it has less energy and a slower combustion rate than
pump Gasoline.

Any advantages are NOT attributed to the cumbustible properties of Propane.

--Perry

On Wed, Apr 10, 2002 at 11:26:03AM +0100, bill.shurvinton at nokia.com wrote:
> Now I am confused.
> 
> In a brief literature search, which left be a little bewildered the following patterns emerged.
> 
> 1. Vapour phase mixing uses reduces HP by 5% beacause of loss of air volume
> 2. Liquid injection offers higher HP than vapour phase (figures of 20% more than petrol have been quoted, 60% in one case!)BUT little/no data on how the injection is carried out.
> 3. Propane has a RON of 112 so needs advanced timing not retarded
> 
> But it would appear that propane systems are still a bit basic in 97% of cases.
> 
> What you are saying about expansion makes sense. I need to do much more research.
> 
> Bill
> 

-- 
Perry Harrington             Linux rules all OSes.               APSoft      ()
perry at apsoft dot com 			                 Think Blue. /\

Those who would give up essential liberty to purchase a little temporary safety
deserve neither liberty or safety. Nor, are they likely to end up with either.
                             -- Benjamin Franklin

----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org