Drag Cars, Drag Tech & Drag Racing Action!

The Explosive Facts About Racing Fuels

Nitromethane Racing Fuel

Nitromethane is a fuel that is used in drag racing to provide maximum power. When you hear the term "Nitro-Burning Funny Car" or "Top Fuel Dragster", that means the engine burns nitromethane fuel. Model aircraft fuel contains about 10% nitromethane.

Nitromethane's chemical formula is CH3NO2. For comparison, gasoline is typically C8H18. The oxygen in nitromethane's molecular structure means that nitromethane does not need as much atmospheric oxygen to burn—part of the oxygen needed to burn nitromethane is carried in the fuel itself.

You need 32.1 pounds of air to burn a 2.2 pounds of gasoline, and only 3.7 pounds of air for the same amount of nitromethane to burn. A cylinder can only hold so much air on each stoke, and with that amount of air you can burn 8.7 times more nitromethane than gasoline. By pumping in 8.7 times as much nitromethane per stroke, you get about 2.4 times more power per stroke. Gasoline provides 18,000 BTU/pound. Nitromethane provides 5,000 BTU/pound. The amount of nitromethane also provides some cooling, making the charge a bit denser and increasing power.

The flame front does not move as quickly in nitromethane as it does in gasoline, meaning that there is not enough time to burn all the nitromethane in the cylinder when the engine is running at high RPM. When the exhaust valve opens, burning nitromethane flows out through the exhaust pipe. That’s why Nitro Motors spit flames from their exhaust pipes.

Nitro Facts

Nitromethane (CH3NO2) is a fuel commonly used in drag racing in both cars and boats.

Nitro fuel burns yellow, the white flames you see at night from the headers is raw burning hydrogen. The flame front of nitro in the combustion chamber is approximately 7050 degrees F. If a cylinder loses spark for a second, nitro fuel accumulates in the cylinder and can cause a massive engine explosion (hydraulic a cylinder), nitromethane does not compress too well. A nitro-burning dragster will use approximately 14-15 gallons of nitro for start-up, staging and a 1/4 mile run.

It is usually use as a mixture with methanol to reduce peak flame temperatures. Its high heat of vaporization results in significant cooling of the air fuel mixture entering an internal combustion engine. The fuel energy of nitromethane is 2.3 times that of iso-octane gasoline for the same mass of air.

The combustion reaction of nitromethane is:

4CH3NO2 +3O2 -> 4CO2 + 6H2O + 2N2

This exothermic reaction results from the strong nitrogen-oxygen bonds. The presence of oxygen in the structure leads to more efficient combustion.

Nitromethane isn't a widely used fuel source since the combustion yields mixtures containing relatively large amounts of nitric acid vapor. The drivers of vehicles fueled by nitromethane (or nitro as the racers refer to it), as well as workers in the starting area must wear gas masks to protect themselves from inhaling the nitric acid vapor.

Nitromethane (MSDS) Material Safety Data Sheet

Methanol Racing Fuel

Methanol, also known as methyl alcohol or wood alcohol, is a chemical compound with chemical formula CH3OH. It is the simplest alcohol, and is a light, volatile, colorless, flammable, poisonous liquid that is used as an antifreeze, solvent, fuel, and as a denaturant for ethyl alcohol.

Methanol is produced naturally in the anaerobic metabolism of many varieties of bacteria. As a result, there is a small fraction of methanol vapor in the atmosphere. Over the course of several days, atmospheric methanol is oxidized by oxygen by the help of sunlight to carbon dioxide and water.

Methanol burns in air forming carbon dioxide and water:

The combustion reaction of methanol is:

2CH3OH + 3 O2 --> 2CO2 + 4H2O

A methanol flame is almost colorless. Care should be exercised around burning methanol to avoid being burned.

Racing Gasoline Basics

The most important characteristic of gasoline is its ''Research Octane Number'' (RON) or octane rating, which is a measure of how resistant gasoline is to premature detonation (engine knocking). It is measured relative to a mixture of (octane/isooctane), (2,2,4-trimethylpentane) and (n-heptane). So an 87-octane gasoline has the same knock resistance as a mixture of 87% isooctane and 13% n-heptane.

There is another type of octane, called "Motor Octane Number" (MON), which is a better measure of how the fuel behaves when under load. Its definition is also based on the mixture of isooctane and n-heptane that has the same performance. Depending on the composition of the fuel, the MON of a modern gasoline will be about 10 points lower than the RON. Normally fuel specifications require both a minimum RON and a minimum MON.

In most countries  (including all of Europe and Australia) the 'headline' octane that would be shown on the pump is the RON, but in the United States and some other countries the headline number is in fact the average of the RON and the MON, sometimes called the "Research Octane Number" or RON. Because of the 10 point difference noted above this means that the octane in the United States will be about 5 points lower than the same fuel elsewhere. 87 octane fuel in the United States would be 92 in Europe.

It is possible for a fuel to have a RON greater than 100. This reflects the fact that isooctane is not the most knock-resistant substance available.  Racing fuels, (Avgas) and (liquefied petroleum gas [LPG]) typically have octane ratings of 110 or significantly higher.

It might seem odd that fuels with higher octane ratings burn less easily, yet are popularly thought of as more powerful.  Using a fuel with a higher octane allows an engine to be run at a higher compression ratio without having problems with knock. Compression is directly related to power, so engines that require higher octane usually deliver more power. Some high-performance engines are designed to operate with a compression ratio associated with high octane numbers, and thus demand high-octane gasoline. It should be noted that the power output of an engine also depends on the energy content of its fuel, which bears no simple relationship to the octane rating.  Some people believe that adding a higher octane fuel to their engine will increase its performance or lessen its fuel consumption.  This is false - engines perform best when using fuel with the octane rating they were designed for.

The octane rating was developed by the chemist Russell Marker. The selection of n-heptane as the zero point of the scale was due to the availability of very high purity n-heptane, unmixed with other isomers of heptane or octane, distilled from the resin of Jeffrey Pine. Other sources of heptane produced from crude oil contain a mixture of different isomers with greatly differing ratings, which would not give a precise zero point.

1968 Chevrolet Camaro RS Hardtop 2-Door 1968 CHEVY CAMARO RS 427/425 HP Motion Phase 3 Tribute Classic Muscle Drag Rare  for sale
1968 Chevrolet Camaro RS Hardtop 2-Door 1968 CHEVY CAMARO RS 427/425 HP Motion Phase 3 Tribute Classic Muscle Drag Rare
$50000.0


1988 Ford Mustang  1988 Ford Mustang Coupe drag race roller, brand new show quality paint job  for sale
1988 Ford Mustang 1988 Ford Mustang Coupe drag race roller, brand new show quality paint job
$8000.0


1994 Ford Mustang  94 Mustang, Drag Car, Prostreet, 10.5 Tire Car, New Build with Trailer  for sale
1994 Ford Mustang 94 Mustang, Drag Car, Prostreet, 10.5 Tire Car, New Build with Trailer
$42000.0


1985 Chevrolet Camaro Z28 Used 85 Chevy Camaro Z28 T-Tops 383 Stroker V-8 Turbo Auto Street Legal Drag MDS  for sale
1985 Chevrolet Camaro Z28 Used 85 Chevy Camaro Z28 T-Tops 383 Stroker V-8 Turbo Auto Street Legal Drag MDS
$12990.0


1972 Chevrolet Nova  1972 Chevrolet Nova, NEW 355ci V8, retro/vintage drag style, new Tires/Wheels  for sale
1972 Chevrolet Nova 1972 Chevrolet Nova, NEW 355ci V8, retro/vintage drag style, new Tires/Wheels
$23400.0


1974 Chevrolet Nova 2Dr. Coupe 1974 CHEVROLET NOVA 2 DR COUPE MUSCLE PERFORMANCE DRAG PROJECT CAR... NO RESERVE  for sale
1974 Chevrolet Nova 2Dr. Coupe 1974 CHEVROLET NOVA 2 DR COUPE MUSCLE PERFORMANCE DRAG PROJECT CAR... NO RESERVE
$202.5


1967 Ford Mustang  1967 Ford Mustang Coupe, Drag Racing Project Car  for sale
1967 Ford Mustang 1967 Ford Mustang Coupe, Drag Racing Project Car
$2800.0


1974 Ford Other Pickups  1974 Ford Wedge Bed Ramp Truck Classic Car Hauler / Drag Racing Hauler / 390  for sale
1974 Ford Other Pickups 1974 Ford Wedge Bed Ramp Truck Classic Car Hauler / Drag Racing Hauler / 390
$5500.0


1980 Chevrolet Monte Carlo  1980 Chevrolet Monte Carlo Pro Street or Drag Car  for sale
1980 Chevrolet Monte Carlo 1980 Chevrolet Monte Carlo Pro Street or Drag Car
$9000.0


1969 Mercury *Drag Pack* Cyclone CJ 428 Super Cobra Jet 1 of 3 69' MERCURY CYCLONE 428CJ *Matching Numbers* Concourse & AACA National Winner  for sale
1969 Mercury *Drag Pack* Cyclone CJ 428 Super Cobra Jet 1 of 3 69' MERCURY CYCLONE 428CJ *Matching Numbers* Concourse & AACA National Winner
$88000.0


1971 Chevrolet C-10 Pro Street 71 Pro Street Supercharged 454 V8 NOS Auto Custom Pickup Show Drag Truck Red  for sale
1971 Chevrolet C-10 Pro Street 71 Pro Street Supercharged 454 V8 NOS Auto Custom Pickup Show Drag Truck Red
$22000.0


1937 Chevrolet COUPE  1937 Chevy Gasser Hot Rod Drag Race Car  for sale
1937 Chevrolet COUPE 1937 Chevy Gasser Hot Rod Drag Race Car
$28500.0


1970 Ford Torino Cobra J-Code 429SCJ Drag Pack J-Code Numbers Matching 429 Super Cobra Jet V8, C6 Automatic, Shaker, Drag Pack  for sale
1970 Ford Torino Cobra J-Code 429SCJ Drag Pack J-Code Numbers Matching 429 Super Cobra Jet V8, C6 Automatic, Shaker, Drag Pack
$54900.0


1968 Chevrolet El Camino  68 el camino tube pro chassis alston drag old super gas car 2600lbs w bbc th400  for sale
1968 Chevrolet El Camino 68 el camino tube pro chassis alston drag old super gas car 2600lbs w bbc th400
$8500.0


1923 Ford Other INSANI
1923 Ford Other INSANI"T" Nostalgia dragster T bucket INSANI"T" Nostalgia dragster T bucket drag car hot rat rod
$3850.0


Get Flash Player

Copyright © 2001-2009 DragCars.com(TM). All Rights Reserved..

Contact Us 

Legal Policy