I've been making my own fuel for years. For a while I was buying some stuff call "Prope" from Klotz. They told me at a show it was propelene oxide. I was adding 0.5% to my fuel. I can tell the difference with and without it. Now Klotz does not sell it and I'm down to my last pint, so what are my other options.

Thanks,

Pete

This is the only info I have on the use of propylene oxide.
"PROPYLENE is used as an ignition accelerator particularly with nitro (up to 20% by volume with pure nitro) where noticeable increases in power are possible. Also promotes easier starting and smoother running when blended with methanol (up to 5%)."

Judging from that, the amount you've been using wouldn't have any noticeable affect. You could try using 3-5% acetone which seems to be quite helpful especially in zero nitro fuels.

Thanks for the good information! I have been mixing my fuel in 4 liter containers (meteric is so much easier to work with). I have been using 2.5 % nitro in my fuel. The "prope" I was getting from Klotz seems to make the engines transition better from low to high RPM. I don't have any data to quantify this but it's just my impression.

I'm going to give acetone a try.

Thank You again,

Pete

Propylene oxide is some very nasty stuff. I would stay away from it. I have not found a need for it in fuel at all. use good clean dry methanol, quality oil and pure nitro adn you will not have a need for any proplyene oxide. Bump up your nitro percentage if you want a similar effect.

How nasty is it? Why would you stay away from it? I used to buy it from Klotz at the Toledo Show. Maybe there is a good reason why they quit selling it.

Pete

extremely extremely volitale

It is said to be a carcinogen. Do a search on propylene oxide and you can find its properties. It can be exploseive under some circumstances.

Jim

"extremely extremely volitale" and "carcinogen"..........Not good for my health both ways, I wont be using it again.

Thank you for the great information,

Pete

Here's the scoup. Propelene oxide was poor man nitro. It contains oxygen like nitro. In earlier racing days fuel was tested for nitro but cheaters found out some prope would pass inspection. Now they test for both and the prope is now the same price as nitro. So useage is way down. Comet cart still sells prope in gallons and will ship. But shipping hazards is pricy.

General
Synonyms: propylene epoxide, 1,2-propylene oxide, methyl oxirane, 1,2-epoxypropane, propene oxide, methyl ethylene oxide, AD 6, 2,3-epoxypropane, methylethylene oxide
Molecular formula: C3H6O
CAS No: 75-56-9
EC No: 200-897-2
Physical data
Appearance: colourless liquid with an ether-like odour
Melting point: -112 C
Boiling point: 34 C
Vapour density: 2 (air = 1)
Vapour pressure: 8.6 psi at 20 C
Specific gravity: 0.83
Flash point: -37 C (closed cup)
Explosion limits: 2.1 - 37 %
Autoignition temperature: 747 C
Water solubility: appreciable

Stability
Stable. Incompatible with acids, bases, oxidising agents, copper, copper alloys, brass, bronze, iron, metal chlorides, peroxides and a wide variety of other materials. Reacts with compounds containing labile hydrogen. Extremely flammable - note low boiling point, low flash point and very wide explosion limits. Moisture sensitive.

Toxicology
Probable human carcinogen. May alter genetic material. May cause impaired fertility. Human mutagenic data. Harmful by ingestion, inhalation and through skin contact. Serious irritant. Very destructive of mucous membranes. Typical TLV/TWA 20 ppm. Typical STEL 100 ppm.
Toxicity data
(The meaning of any abbreviations which appear in this section is given here.)
ORL-RAT LD50 380 mg kg-1
IHL-MUS LC50 1740 ppm/4h.
IPR-RAT LD50 150 mg kg-1
IHL-DOG LCLO 2005 ppm/4h
ORL-GPG LD50 6600 mg kg-1
IPR-RAT LD50 364 mg kg-1
SKN-RBT LD50 1500 mg kg-1

Risk phrases
(The meaning of any risk phrases which appear in this section is given here.)
R12 R20 R21 R22 R36 R37 R38 R45.


Transport information
(The meaning of any UN hazard codes which appear in this section is given here.)
UN Major hazard class: 3.0. Packing group: I. UN No 1280.

Personal protection
Safety glasses, gloves, good ventilation. Remove all sources of ignition from the working area. Treat as a carcinogen.
Safety phrases
(The meaning of any safety phrases which appear in this section is given here.)
S45 S53.

our methanol (I'm in Greece) has 5% toluol (tolyene) in it. I don't use nitromethane.
I was adding 3% aceton for a long time until someone said that toluol has the same effect as acetone.
and this amount (8%) would higher the engine temp.
it actually did.even without acetone it does. but should I add acetone for some reason? i didn't saw any performance differences though.

btw.
pure methanol or nitromethane in a reasonable price is impossible to find here.

tdriver,
you will be just fine without adding acetone, there is no need with the methanol you describe as having toluol in it.

I see, thanks.
are there any other "side effects" toluol may have compared to same fuel without toluol in it?
I did ones a comparsion with the same mix but wih pharmaceutical methanol (99.98% purity)
I noticed much crispier accelation with it. (99.98%) and the sound was also a little heavier. (more bass)
could this difference be a effect of the toluol , or is this a sign that water is in the fuel?
I have tried many times to figure that out,but no luck .

tdriver,
Acetone and toluol are both going to change the flame speed and combustion temp properties. I'm not too sure about the specifics as to which is best and frankly it really does not matter since it (toluol) is already in the methanol and you are pleased with the results.
The differences in your test could be anything, including needle settings which will more than likely be different with and without the mentioned additives in it. Its hard to say.