Grand National (GNRA)

Grand National Specifications

Length: 25 feet maximum

Weight: No Minimum (average approx. 2500 lbs.)

Hull: Mono Hull - vee / flatbottom

Propulsion: American-made automotive engine mounted to rear of amidships and driving forward through a v-drive to a stationary strut mounted propeller.
Gearboxes are permitted.

The GN Engine:
Block: Chevrolet Big Block, Chrysler B/ RB or Chrysler Hemi-based engines. Cast iron engine blocks only.

Cylinder Heads: OEM or aftermarket. Iron or aluminum with common wall intake ports.

Cam/lifters: In-block, any style. No overhead cams.

Oiling System: Any

Cubic Inches Limits: Supercharged = 475C.I. max.
Naturally Aspirated = 525 C.I. max.

Blower: Must be Roots type Blower

Max. Overdrive:

8-71: 1.03:1

10-71: 0.95:1

14-71: 0.83:1

Fuel: Gasoline only, no additives(nitro)

Induction: Any (except Turbochargers). Intake manifold must be cast (no sheet metal)

Ignition: Any

Estimated Horsepower: 875-925

Estimated Top Speed: 100+