I've seen several comments asking about fuel additives lately.
Here's some info gleaned from some of the lists recently..
I hope the non-brit technical content translates well, :-)
From: cernada@ait.com (Joseph P. Cernada)
Subject: octane stuff
> One last request: Let's summarize octane boosters. Toluene can be
> used, what else? Benzene (that's the deadly stuff right)? Gotta
> find a local chemical supply for a friend's 1960's big block Olds
> engine.
The following was posted on the hotrod mailing list/newsgroup:
======================================================================
>From: "KEN MOSHER" <Ken_Mosher@imd.sterling.com>
Subject: Gasoline and about last nig
With all the talk about O2 sensors, oxygenated fuels, and racing gas, I decided
to dig up the following data that I've gathered. I hope it is of general
interest to the list.
First, some data about the Sunoco CAM2 fuels from their literature:
SUNOCO "Standard"
Color......................Purple
Research Octane.........115
Motor Octane..............107
R+M/2 ......................111
Specific Gravity........0.725
Reid Vapor Pressure..... 8#
-- Distallation temp, degrees F --
Initial............90
10%............160
50%............220
Final...........360
SUNOCO "GT Unleaded"
Color......................Natural
Research Octane.........105
Motor Octane..............95
R+M/2 ......................100
Specific Gravity........0.760
Reid Vapor Pressure..... 8#
-- Distallation temp, degrees F --
Initial............90
10%............150
50%............210
Final...........230
SUNOCO "Supreme"
Color......................Blue
Research Octane.........116
Motor Octane..............109
R+M/2 ......................112
Specific Gravity........0.715
Reid Vapor Pressure..... 8#
-- Distallation temp, degrees F --
Initial............90
10%............155
50%............215
Final...........260
SUNOCO "Maximal"
Color......................Red
Research Octane.........118
Motor Octane..............115
R+M/2 ......................117
Specific Gravity........0.700
Reid Vapor Pressure..... 6#
-- Distallation temp, degrees F --
Initial............100
10%............150
50%............220
Final...........240
And from Rich Lassitter's article in the GS Xtra ... how to mix your own brew:
Formula #1 - Toulene
=============================
R+M/2.........114
Cost...........$2.50/gal
Mixtures with 92 Octane Premium
--------------------------------
10%...........94.2 Octane
20%...........96.4 Octane
30%...........98.6 Octane
Notes: Common ingredient in Octane Boosters in a can. 12-16 ounces will only
raise octane 2-3 *points*, i.e. from 92 to 92.3. Often costs $3-5 for 12-16
ounces, when it can be purchased for less than $3/gal at chemical supply houses
or paint stores.
Formula #2 - Xylene
=============================
R+M/2.........117
Cost...........$2.75/gal
Mixtures with 92 Octane Premium
--------------------------------
10%...........94.5 Octane
20%...........97.0 Octane
30%...........99.5 Octane
Notes: Similar to Toulene. 12-16 ounces will only raise octane 2-3 *points*,
i.e. from 92 to 92.3. Usually mixed with Toulene and advertised as *race
formula*.
Formula #3 - Methyl-tertiary-butyl-ether (MTBE)
=============================
R+M/2.........118
Cost...........$3.50/gal
Mixtures with 92 Octane Premium
--------------------------------
10%...........94.6 Octane
20%...........97.2 Octane
30%...........99.8 Octane
Notes: Oxygenate. Very common in octane booster products. Has lower BTU
content than toulene or xylene, but oxygenate effect makes the gasoline burn
better and produce more energy.
Formula #4 - Methanol or Ethanol
=============================
R+M/2.........101
Cost...........$0.60 - $1.75/gal
Mixtures with 92 Octane Premium
--------------------------------
10%...........94.3 Octane (Methanol)
10%...........94.7 Octane (Ethanol)
20%...........Not Recommended
Notes: Methanol is wood alcohol. Ethanol is grain alcohol and found in Gasohol
in 10% ratios. Both alcohols are mildly corrosive and will eat gas tank
linings, rubber and aluminum if used in excessive ratios. Main ingredient in
"Gas Dryers", combine with water.
Formula #5 - Isopropyl Alcohol and Tertiary Butyl Alcohol
=============================
R+M/2.........101
Cost...........$0.60-$1.50/gal
Mixtures with 92 Octane Premium
--------------------------------
10%...........94.5 Octane
20%...........Not Recommended
30%...........Not Recommended
Notes: Similar to Methanol/Ethanol. Isopropyl Alcohol is simply rubbing
alcohol.
How to make your own octane booster (this is the basic formula of one of the
popular octane booster products). To make eight 16 ounce bottles (128 oz = 1
gal):
100 oz of toulene for octane boost
25 oz of mineral spirits (cleaning agent)
3 oz of transmission fluid (lubricating agent)
This product is advertised as "octane booster with cleaning agent *and*
lubricating agent!". Diesel fuel or kerosene can be substituted for mineral
spirits and light turbine oil can be substituted for transmission fluid. Color
can be added with petroleum dyes.
-- Ken Mosher
From: davet@interceptor.cds.tek.com
Subject: Re: octane stuff
> > 100LL avgas was invented to allow the engines in older light
> > planes, which used 80 octane unleaded avgas, to get fuel from the same
> > pump as more modern stuff. 80/88 unleaded avgas is obsolete.
>
> If the older aircraft engines needed unleaded, what's the lead for in
> the 100LL? Just to get the octane up for the newer engines?
Regular 'ol 100/108 avgas has so much lead that it causes
lead-fouling in low-compression older engines. 100LL was invented so
that old engines wouldn't foul, and new engines wouldn't detonate. It
wasn't entirely successful in either department.
> > at all to prevent detonation, but the pump gas is so full of low-heat
> > additives, that the racing fuel actually makes considerably more power.
>
> Please explain what "low-heat" additives are/do.
I'm referring to the specific heat of combustion, the measure of
how much energy is produced to propel the vehicle when the fuel is
burned. MTBE is added in enormous quantities in Denver in the winter,
15% by volume. It has a nice high octane rating, but the actual amount
of energy it releases when burned is very low. Most drivers find that
their mileage is reduced by about 10% when the MTBE is in there. This
is because the engine produces 10% less power at a given throttle
setting, so they run at higher throttle settings. Ethanol is just about
as bad, and methanol is slightly better (although it will destroy your
engine). Detergents and the stuff they use to prevent alcohol from
separating from gasoline in the presence of water also reduce the energy
content of the fuel.
Some fuel companies are putting MTBE in their unleaded premium gas
all the time everywhere, because it improves the octane rating and is
cheaper than real gasoline. Take unleaded regular, dilute with MTBE,
presto you get unleaded premium with less energy content than the
regular, but with higher octane rating. Phillips Petroleum does this.
> One last request: Let's summarize octane boosters. Toluene can be
> used, what else? Benzene (that's the deadly stuff right)? Gotta
> find a local chemical supply for a friend's 1960's big block Olds
> engine.
Benzine is the old drag-racer's "cheater fuel" additive because it
not only improves octane, but combusts with more energy than gasoline.
It's quite carcinogenic, and is poisonous to drink, but is otherwise not
too bad. Like most other solvents, it can get absorbed through the
skin, so you shouldn't bathe in it. Makes the fuel smell funny too,
although not as bad as MTBE.
emd@ham.almanac.bc.ca (Robert Smits, Ladysmith B.C.)
Hellers Law
The first myth of management is that it exists.
|