AVAILABLE NJBA CLASSES AND REQUIREMENTS

All/
FLAT/
HYDRO/
JET/

Ski Jets are intended to be jet boats having typical water skiing equipment and appearance. Internal engine modifications are permitted to enhance competition and reliability.

GENERAL

  1. Seating must accommodate a minimum of two (2) adults. Seats must be fully upholstered, and at minimum must consist of a full width bench seat and back, or two (2) equal bucket seats.
  2. Steering wheel must be a minimum of 8” off hull center line.
  3. Boats may have any type of nozzle with a functional neutral mechanism that is operational from the driver’s seat.
  4. Adjustable cavitation plates are permitted.
  5. Fuel is restricted to racing gasoline.

ENGINE

  1. Any bore and stroke combination is allowed up to a maximum of 460 cubic inches, with a clean-up hone of a maximum of .005 inches.
  2. No aluminum blocks allowed.
  3. Any carburetor configuration up to a maximum of 1500 C.F.M. Absolutely no modifications to the venturi area are permitted on any carburetor from air cleaner flange to base plate, i.e., any factory casting flash and cadmium plating. Visual inspection by the Technical Committee will be allowed at their discretion.
  4. The Tech Committee must approve all carburetors.
  5. Ski Jets may run any type of exhaust.
  6. Intake manifold must be cast production or modified production only. No homemade or non-production manifolds allowed.
  7. Pro Stock style cylinder heads are prohibited. Intake port spacing must remain in stock OEM location as manufactured for production vehicles.
  8. 2 speed transmissions are prohibited.

Modified Jets are intended to be jet boats used specifically for racing, and limited only to maintain a similarity in racing equipment.

GENERAL

  1. Any modification to boat, engine or jet, not specifically prohibited, is permitted.
  2. Fuel is restricted to racing gasoline.

ENGINE

  1. Any bore and stroke combination is allowed up to a maximum of 482 cubic inches.
  2. Engine must be naturally aspirated.
  3. Pro Stock style cylinder heads are prohibited. Intake port spacing must remain in stock OEM location as manufactured for production vehicles.

Comp Jets are intended to be jet boats used specifically for racing, and limited only to maintain a similarity in racing equipment.

GENERAL

  1. Any modification to boat, engine or jet, not specifically prohibited, is permitted.
  2. Fuel is restricted to racing gasoline.

ENGINE

  1. Maximum engine displacement is 470 cubic inches.
  2. Engine must be naturally aspirated.

Pro Gas Jets are intended to be jet boats used specifically for racing and limited only to maintain a similarity in racing equipment.

GENERAL

  1. Any modification to boat, engine or jet, not specifically prohibited, is permitted.
  2. Fuel is restricted to racing gasoline.

ENGINE

  1. Maximum engine displacement for tunnel boats is 515 cubic inches.
  2. Maximum engine displacement for non-tunnel boats is 565 cubic inches.
    • BBC engines are limited to cylinder heads with an intake valve angle of 24 degrees.
    • Ford engines are limited to cylinder heads with the same intake valve angle as the O.E.M 460 cylinder head.
    • Mopar engines are limited to cylinder heads with the same intake valve angle as the O.E.M. 440 Mopar or 426 Hemi heads.
    • All cylinder heads and engines are subject to approval by the N.J.B.A. Tech Committee.
  3. Engine must be naturally aspirated.

Unblown Fuel Jets are intended to be jet boats used specifically for racing, and limited only to maintain a similarity in racing equipment.

GENERAL

  1. Gasoline, methanol, and nitromethane are permitted.
  2. Nitrous oxide is permitted.

ENGINE

  1. Maximum cubic inch is unlimited.

Blown Gas Jets are intended to be jet boats used specifically for racing, but having highly unusual, expensive or experimental equipment.

GENERAL

  1. Fuel is restricted to racing gasoline.

ENGINE

  1. Blowers or turbo-chargers are mandatory.
  2. Maximum engine displacement is 572 cubic inches.
  3. Water injection is allowed on blown gas engines providing a sufficient amount of liquid remains in the tank, which will be used for testing purposes at the end of each run.

Blown Fuel Jets are intended to be jet boats used specifically for racing, but having highly unusual, expensive or experimental equipment.

GENERAL

  1. Any type fuel is permitted, other than gasoline.
  2. A maximum of 50% nitromethane allowed.

ENGINE

  1. Blowers or turbo-chargers are mandatory.
  2. Maximum engine displacement is 565 cubic inches.
  3. Blower belts must be Kevlar and 14mm in size.

PRESSURE RELIEF VALVE REQUIREMENTS

  1. All Blown Fuel Jets must have a pressure relief valve attached to the intake side of the pump bowl. A pressure gage at the intake side of the impeller must be installed within 2” of the packing nut with a check ball or talletale type unit attached (0-200 lbs.).
  2. A manual override button on the steering wheel is required.
  3. The valve must open in an automatic fashion in case of engine failure or some other type of uncontrolled emergency.
  4. The valve will be inspected at the in-ramp prior to each run.
  5. Once valve is opened, it must remain open until the boat is on the trailer.
  6. Piston size:
    • Minimum 4” diameter.
    • 13 sq. inches minimum unrestricted exhaust opening.

Ski Flats are intended to be prop driven flat bottom boats having typical water skiing equipment and appearance. Internal engine modifications are permitted to enhance competition and reliability.

GENERAL

  1. Seating must accommodate a minimum of two (2) adults. Seats must be fully upholstered, and at minimum, consist of a full width bench seat and back, or two (2) equal bucket seats.
  2. Steering wheel must be a minimum of 8” inches off hull center line.
  3. Fuel is restricted to racing gasoline.

ENGINE

  1. Any bore and stroke combination is allowed up to a maximum of 460 cubic inches, with a clean-up hone of a maximum of .005 inches.
  2. No aluminum blocks allowed.
  3. Any carburetor configuration up to a maximum of 1500 C.F.M. Absolutely no modifications to the venturi area are permitted on any carburetor from air cleaner flange to base plate, i.e., any factory casting flash and cadmium plating. Visual inspection by the Technical Committee will be allowed at their discretion.
  4. The Tech Committee must approve all carburetors.
  5. Ski Flats may run any type of exhaust.
  6. Intake manifold must be cast production or modified production only. No homemade or non-production manifolds allowed.
  7. Pro Stock style cylinder heads are prohibited. Intake port spacing must remain in stock OEM location as manufactured for production vehicles.
  8. 2 speed transmissions are prohibited.

Comp Flats are prop driven flat bottoms used specifically for racing.

GENERAL

  1. Fuel is restricted to racing gasoline.

ENGINE

  1. Displacement may not exceed 470 C.I.D.
  2. Engine must be naturally aspirated.

Pro Gas Flats are prop driven flat bottoms used specifically for racing.

GENERAL

  1. Fuel is restricted to racing gasoline.

ENGINE

  1. Displacement may not exceed 515 C.I.D.
  2. Engine must be naturally aspirated.

Pro Comp Flats are prop driven flat bottoms used specifically for racing. No Capsules Boats.

GENERAL

  1. This class maximum allowed ET index is 6.50 seconds
  2. Fuel is unrestricted
  3. The only exception is that Blown Fuel Flats are not legal for this class

ENGINE

  1. Displacement is unlimited.
  2. Motors may be naturally aspirated, blown, pro charged, or turbo-charged.

Blown Gas Flats are intended to be race boats used specifically for racing, but having highly unusual, expensive or experimental equipment.

GENERAL

  1. All boats shall have installed a device making possible the engagement and disengagement “at will” of the propulsion device while the engine is running.
  2. Fuel is restricted to racing gasoline.

ENGINE

  1. Maximum engine displacement is 572 cubic inches.
  2. Water injection is allowed on blown gas engines providing a sufficient amount of liquid remains in the tank, which will be used for testing purposes at the end of each run.
  3. Blowers or turbo-chargers are mandatory.

Top Alcohol Flats are intended to be race boats used specifically for racing, but having highly unusual, expensive or experimental equipment.

GENERAL

  1. Fuel system – Mechanized fuel system allowed. The injection system cannot be controlled by exhaust gasses.
  2. Fuel – Blown methanol. Unblown nitromethane, no percentage limit.
  3. Clutch, Flywheel & Bellhousing – All boats utilizing a clutch must have a S.F.I. 6.1, 6.2, or 6.3 hydroformed bellhousing. All boats must have a 360 degree flywheel cover.
  4. Neutral Device – A devise to allow engagement and disengagement “at will” of the propulsion device while the engine is running is mandatory.
  5. Prop shaft – The minimum prop shaft diameter through the back of the strut is 1- 1/8”.

ENGINE

  1. Any internal combustion automotive type engine permitted. No dual engine set-ups allowed. Maximum 572 cubic inch and 4 valves per cylinder.
  2. Supercharger – Required – roots-type maximum size 14-71, 19” case length, 11-1/4” case width, maximum rotor cavity diameter is 5.840”. Helix is restricted to maximum rotor spiral of 6.5 degrees per inch of length. Maximum overdrive 70%.
  3. Screw-type superchargers are not allowed.

Blown Fuel Flats are intended to be race boats used specifically for racing, but having highly unusual, expensive or experimental equipment.

GENERAL

  1. Fuel system – Mechanized fuel system allowed. The injection system cannot be controlled by exhaust gasses.
  2. Fuel – 50% nitro-methane and 50% methanol only. No other chemicals or additives are permitted.
    • Random fuel checks may occur any time during qualifying or eliminations.
    • Refusal of any fuel sample will result in disqualification for the entire race
  3. Clutch, Flywheel & Bell-housing – All boats utilizing a clutch must have a S.F.I. 6.1, 6.2, or 6.3 hydroformed bellhousing. Boats utilizing a “dry clutch” must have a SFI approved clutch can. All boats must have a 360 degree flywheel cover.
  4. Neutral Device – A device to allow engagement and disengagement “at will” of the propulsion device while the engine is running is mandatory.
  5. Prop shaft – The minimum prop shaft diameter through the back of the strut and the propeller is 1 1/8 inches. Cut down shafts are not allowed.
    • Maximum diameter of the propeller is 11 inches.
  6. Capsule – All boats must have capsules approved by the N.J.B.A.
  7. License – All drivers new to this class must be licensed by the N.J.B.A. a. All drivers will be required to successfully launch their boat, make a half track pass, and a successful full pass before being licensed.
  8. Coarse – BFF’s will run a 1000 foot course.

ENGINE

  1. Maximum cubic inch is 565.
    • Engines may run one magneto only. Dual magnetos are not allowed.
  2. Supercharger – Root type blowers up to 14-71 are allowed. Screw type blowers are not allowed.
    • Intake manifold must have “burst panels.”
    • All blower bags must adhere to SFI 14.2 specifications

Ski Hydros are intended to be prop driven flat bottom boats having typical water skiing equipment and appearance. Internal engine modifications are permitted to enhance competition and reliability.

GENERAL

  1. Seating must accommodate a minimum of two (2) adults. Seats must be fully upholstered, and at minimum, consist of a full width bench seat and back, or two (2) equal bucket seats.
  2. Steering wheel must be a minimum of 8” off hull center line.
  3. Fuel is restricted to racing gasoline.

ENGINE

  1. Any bore and stroke combination is allowed up to a maximum of 460 cubic inches, with a clean-up hone of a maximum of .005 inches.
  2. No aluminum blocks allowed.
  3. Any carburetor configuration up to a maximum of 1500 C.F.M.
  4. Absolutely no modifications to the venturi area are permitted on any carburetor from air cleaner flange to base plate, i.e., any factory casting flash and cadmium plating. Visual inspection by the Technical Committee will be allowed at their discretion.
  5. The Tech Committee must approve all carburetors.
  6. Ski Hydros may run any type of exhaust.
  7. Intake manifold must be cast production or modified production only. No homemade or non-production manifolds allowed.
  8. Pro Stock style cylinder heads are prohibited. Intake port spacing must remain in stock OEM location as manufactured for production vehicles.
  9. 2 speed transmissions are prohibited.

Comp Hydros are intended to be race boats used specifically for racing and limited only to maintain a similarity in racing equipment.

GENERAL

  1. Any modification to boat or engine not specifically prohibited is permitted.
  2. The minimum prop shaft diameter through the back of the strut shall be 1-1/8”.
  3. Fuel is restricted to racing gasoline.

ENGINE

  1. Maximum engine displacement is 470 cubic inches.
  2. Engine must be naturally aspirated.

Pro Gas Hydros are intended to be race boats used specifically for racing and limited only to maintain a similarity in racing equipment.

GENERAL

  1. Any modification to boat or engine not specifically prohibited is permitted.
  2. The minimum prop shaft diameter through the back of the strut shall be 1-1/8”.
  3. Fuel is restricted to racing gasoline.

ENGINE

  1. Maximum engine displacement is 515 cubic inches.
  2. Engine must be naturally aspirated.

Blown Gas Hydros are intended to be race boats used specifically for racing and limited only to maintain a similarity in racing equipment.

GENERAL

  1. Any modification to boat or engine not specifically prohibited is permitted.
  2. The minimum prop shaft diameter through the back of the strut shall be 1-1/8”.
  3. Fuel is restricted to racing gasoline.

ENGINE

  1. Maximum engine displacement is 572 cubic inches.
  2. Blowers or turbo-chargers are mandatory.

GENERAL

  1. Fuel System – Mechanized fuel systems allowed. The injection system cannot be controlled by exhaust gasses.
  2. Fuel – Gasoline, methanol and/or nitrous oxide allowed. Propylene oxide will not be allowed.
  3. Clutch, Flywheel and Bell-housing – All boats must have a 360-degree flywheel cover.
  4. Neutral Device – A device to allow engagement and disengagement “at will” of the propulsion device while the engine is running.
  5. Prop Shaft – 1-1/8” shaft diameter on front portion of prop shaft may not be reduced to less than 1-1/8”. If a two-piece prop shaft is utilized, the coupler must meet the following criteria:
    1. Thru-bolt coupler bolt must be indexed into prop shaft. The bolt must be the same size as the hole in the coupler.
    2. Split coupler with set screw retainment, prop shaft must be dimpled with drill bit that will fit into set screw hole in coupler the full depth of the drill point. Set screw must be secured in the hole.
    3. No barrel drilling of prop shaft allowed.
  6. Rudder – All Hydro rudders must extend 1-1/2” past the lowest point of the propeller. Chrome rudders will not be allowed.
  7. Index – 5.60

ENGINE

  1. Any internal combustion automotive-type engine permitted. No dual engine set-ups allowed.

GENERAL

  1. Fuel System – Mechanized fuel systems allowed. The injection system cannot be controlled by exhaust gasses.
  2. Fuel – Gasoline, methanol and/or nitrous oxide allowed. Propylene oxide will not be allowed.
  3. Clutch, Flywheel and Bell-housing – All boats must have a 360-degree flywheel cover.
  4. Neutral Device – A device to allow engagement and disengagement “at will” of the propulsion device while the engine is running.
  5. Prop Shaft – 1-1/8” shaft diameter on front portion of prop shaft may not be reduced to less than 1-1/8”. If a two-piece prop shaft is utilized, the coupler must meet the following criteria:
    1. Thru-bolt coupler bolt must be indexed into prop shaft. The bolt must be the same size as the hole in the coupler.
    2. Split coupler with set screw retainment, prop shaft must be dimpled with drill bit that will fit into set screw hole in coupler the full depth of the drill point. Set screw must be secured in the hole.
    3. No barrel drilling of prop shaft allowed.
  6. Rudder – All Hydro rudders must extend 1-1/2” past the lowest point of the propeller. Chrome rudders will not be allowed.
  7. Index – 5.20

ENGINE

  1. Any internal combustion automotive-type engine permitted. No dual engine set-ups allowed.

GENERAL

  1. Fuel System – Mechanized fuel system allowed. The injection system cannot be controlled by exhaust gasses.
  2. Fuel – Blown Methanol. Unblown Nitromethane, no percentage limit.
  3. Clutch, Flywheel and Bell-housing – All boats utilizing a clutch must have a S.F.I. 6.1, 6.2, or 6.3 hydroformed bellhousing. All boats must have a 360-degree flywheel cover.
  4. Neutral Device – A device to allow engagement and disengagement “at will” of the propulsion device while the engine is running.
  5. Prop Shaft – The minimum prop shaft diameter through the back of the strut is 1- 1/8”.
  6. Rudder – Minimum 5/8 inch thickness at the clamshell.

ENGINE

  1. Any internal combustion automotive type engine permitted. No dual engine set-ups allowed. Maximum 572 cubic inch and 4 valves per cylinder.
  2. Supercharger – Required – roots-type maximum size 14-71, 19” case length, 11-1/4” case width, maximum rotor cavity diameter is 5.840”. Helix is restricted to maximum rotor spiral of 6.5 degrees per inch of length. Maximum overdrive 70%.
  3. Screw-type superchargers are allowed.

GENERAL

  1. Fuel System – Mechanized fuel system allowed. The injection system cannot be controlled by exhaust gasses.
  2. Fuel – A minimum of 50nitromethane.
  3. Clutch, Flywheel and Bell-housing – All boats utilizing a clutch must have a S.F.I. 6.1, 6.2, or 6.3 hydroformed bellhousing. All boats must have a 360-degree flywheel cover.
  4. Neutral Device – A device to allow engagement and disengagement “at will” of the propulsion device while the engine is running.
  5. Prop Shaft – The prop shaft diameter through the back of the strut is 1-3/8”. The minimum for duel prop shaft boats is 1-1/4”.
  6. Rudder – All rudder support brackets must be solid, no lightening holes will be allowed. Brackets at each side of clamshell must be a minimum of 5/8” thick. Any lightening holes in any rudder support brackets will not be allowed. The rudder must have a minimum thickness of 5/8 of an inch.
  7. Parachute – Mandatory.
  8. Safety Capsule – Mandatory.

ENGINE

  1. Any internal combustion automotive type engine permitted. No dual engine set-ups allowed. Maximum 565 cubic inch and 4 valves per cylinder.
  2. Supercharger – Required – roots-type maximum size 14-71, 19” case length, 11-1/4” case width, maximum rotor cavity diameter is 5.840”. Helix is restricted to maximum rotor spiral of 6.5 degrees per inch of length. Manifold burst panels meeting SFI Spec 23.1, plus restraint system meeting SFI Spec 14.2 mandatory. Screw-type superchargers prohibited.

Unlimited Outlaw

GENERAL

  1. Unlimited Outlaw is open to all open cockpit boats
  2. Race Course is 660 Feet (1/8 Mile)
  3. Capsule boat are porhibited
  4. General racing rules apply
  5. Speed limits apply

ENGINE

  1. Displacement is unlimited
  2. Motors may be naturally aspirated, blown, pro charged, or turbo-charged.

PRO COMP HYDRO

Pro Comp Hydro are prop driven flat bottoms used specifically for racing.

GENERAL

  1. This class maximum allowed et index is 6.50 second
  2. Fuel is unrestricted
  3. Race course is 1000′

ENGINE

  1. Displacement is unlimited
  2. Motors may be naturally aspirated, blown, pro charged, or turbo-charged.