VP Racing C15 Fuel

VP Racing C15 is a 117-octane, leaded, non-oxygenated race fuel formulated for large-cubic-inch, naturally aspirated race engines with ultra-high compression ratios.

C15 is designed primarily for 500 cubic-inch and larger engines operating at 14:1 compression or greater. Its high-octane, non-oxygenated formulation provides the detonation resistance these demanding big-block combinations need while maintaining predictable fuel chemistry for consistent tuning.

C15 can also be used in smaller nitrous-assisted engine combinations when the engine builder or tuner specifies a fuel with this octane level and combustion profile. With 0% oxygen content, C15 avoids the added fuel-calibration changes that can come with oxygenated race fuels.

This leaded fuel is green for easy identification and is available in 5-gallon pails and 54-gallon drums. C15 is intended for off-road and competition use where permitted.

Fuel specifications

• Fuel type: Leaded race fuel

• Octane rating: 117 (R+M)/2

• Motor Octane Number: 115

• Research Octane Number: 119

• Oxygen content: 0%, non-oxygenated

• Recommended engines: 500+ cubic-inch naturally aspirated engines with 14:1+ compression

• Additional application: Smaller nitrous-assisted engine combinations

• Specific gravity: 0.7130

• Reid vapor pressure: 3.93 psi

• Stoichiometric air-fuel ratio: 14.88

• Oxidation stability: 1,440+ minutes

• Color: Green

Recommended applications

• Large-displacement naturally aspirated race engines

• 500+ cubic-inch big-block racing combinations

• Engines with compression ratios of 14:1 or greater

• Smaller nitrous-assisted engine applications

• Drag racing and other competition engines requiring high-octane, non-oxygenated leaded fuel

Frequently asked questions

What is VP C15 fuel?

VP C15 is a 117-octane, leaded, non-oxygenated race fuel formulated for large naturally aspirated engines with ultra-high compression ratios. It is primarily recommended for 500 cubic-inch and larger engines operating at 14:1 compression or greater.

What size engine is VP C15 designed for?

C15 is designed primarily for naturally aspirated engines with displacement of 500 cubic inches or more. It is intended for large-cubic-inch combinations that require substantial detonation protection.

What compression ratio is VP C15 recommended for?

VP C15 is recommended for naturally aspirated race engines with compression ratios of 14:1 or greater. Fuel selection should always consider the complete engine combination, including compression, RPM, ignition timing, cylinder-head design, and induction system.

Can VP C15 be used with nitrous?

Yes. VP states that C15 can be used in smaller nitrous-assisted engine combinations. Follow your engine builder's or tuner's fuel recommendation for the specific nitrous system, power level, and engine setup.

Is VP C15 oxygenated?

No. C15 contains 0% oxygen. Its non-oxygenated chemistry helps provide predictable combustion behavior without the additional fuel-calibration changes associated with oxygenated race fuels.

Is VP C15 leaded?

Yes. C15 is a leaded race fuel. Confirm that leaded fuel is compatible with your engine, fuel system, oxygen sensors, catalytic converter, and racing-class regulations before use.

What is the octane rating of VP C15?

VP C15 has a 117 (R+M)/2 octane rating, with a 115 MON and 119 RON.

How is C15 different from C14 Plus?

Both fuels are leaded, non-oxygenated, and rated at 117 octane. C15 is specifically formulated for large, 500+ cubic-inch naturally aspirated engines with 14:1+ compression and can also be used in smaller nitrous combinations. C14 Plus is intended for the same general high-compression applications as C14, while providing additional detonation protection over C14.

Is VP C15 street legal?

C15 is a leaded racing fuel intended for off-road and competition use where permitted. Follow all applicable emissions laws, fuel regulations, and racing-series rules.