Honda-The Power of Dreams
Honda to Test Natural Gas-Powered Civic with "Almost Zero" Emissions

Tokyo, February 17, 1997 --- Honda announced today it has developed a compressed natural gas-powered "Civic GX". Producing "almost zero" exhaust emissions, this car will be tested on public roads starting this month prior to being made available to the general public. In addition to its inherently clean nature, natural gas is also available in even larger quantities than petrol. It is also familiar as home-use gas.

Honda Motor has been researching cleaner vehicles over a long period of time. Building on this foundation, we wanted to further push the limits for natural gas-powered vehicles and add the Civic GX to Honda's fast growing family of alternative fuel and clean air vehicles.

Using a VTEC-E engine, the Civic GX combines dramatically lowered emission with performance on a par with gasoline-engined cars. To solve the cruising range problem associated with natural gas-powered vehicles before now, we have adopted an all-composite fuel tank. The advantages are one-third the weight of an aluminum equivalent while offering a driving range similar to that of gasoline-powered cars at 400km on one full tank.

The tank itself has been located in an area of the trunk providing enough crushable zone in rear end collisions. A rigid body structure further adds to passenger safety. Combining the tank, its high pressure plumbing and related accessories into one single module has also made mass production possible.

Compressed Natural Gas Civic GX
Compressed Natural Gas Civic GX

Civic GX emissions vs. Japanese emission regulations

Civic GX (in-house data) 0.949 0.38 0.0619
Authorized maximum (max) 85.0 9.50 6.00
Authorized average (ave) 60.0 7.00 4.40
Civic GX vs. (ave) -98.4% -94.6% -98.6%
Civic GX (in-house data) 0.001 0.002 0.022
Authorized maximum (max) 2.70 0.39 0.48
Authorized average (ave) 2.10 0.25 0.25
Civic GX vs. (ave) -99.9% -99.2% -91.2%
* 11-mode in suburb-town in-bound test course with cold start.
** 10.15-mode includes 10-mode Tokyo in-town main road average course and 15-mode highway to slow traffic course, more representative of big city traffic.

Main technical features
  • VTEC-E engine for high power and low emissions.
  • High 12.5:1 compression ratio taking advantage of the high Compressed Natural Gas (CNG) octane number.
  • Safety valve technology from Honda's Indy program (methanol fuel).
  • High precision/high response electronically controlled multi-point fuel injectors.
  • Compact, lightweight, high precision accumulative fuel pressure regulator.
  • All-composite CNG tank for lightweight and extended driving range.
  • Modular CNG tank construction for mass production capability.
  • Self-sealing tank orifice seal.
  • In-tank fuel supply breaker vane.
  • Tank layout allowing sufficient crushable zone + rigid body structure.


Engine capacity 1,590cc
Maximum Power 115ps/6,500rpm
Maximum torque 13.6kgm/5,500rpm
Maximum speed 176 km/h
Curb weight 1,165kg
Fuel tank material All-composite
Fuel tank size 120 liters
Range on one tank 400km (in-house data)