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Junior classes

 

J Hydroplane/Runabout

Displacement: 13.2 c.i. or 15.9 c.i.
Permitted engines:
• OMC 13.2 c.i., 2 cylinder with 0.5″ carburator restrictor plate
• OMC 15.9 c.i., 2 cylinder with 0.5″ carburator restrictor plate
• Mercury 60-J 15.9 c.i., 2 cylinder

Straightway speed range: 35-40 mph

Minimum Age Req: 9 Years Old

 

 

AX Stock Hydroplane/Runabout

Displacement: 13.2 c.i. or 15.9 c.i.
Permitted engines:
• OMC 13.2 c.i., 2 cylinder with 0.65″ carburator restrictor plate
• OMC 15.9 c.i., 2 cylinder with no carburator restrictor plate
• Mercury 60-J 15.9 c.i., 2 cylinder

Straightway speed range: 40-45 mph

Minimum Age Req: 12 Years Old

 

Modified classes

 

200cc Modified Hydroplane/Runabout (Formula A)

Displacement: 13.2 c.i.
Permitted engines:
• OMC 13.2 c.i., 2 cylinder

Straightway speed range: 55-60 mph

Minimum Age req: 14

 

 

 

 

250cc Modified Hydroplane/Runabout (A Mod)

Displacement: 15 c.i.
Permitted engines:
• Swanson Champion-American Hot Rod, 15 c.i.
• Mercury KG4H, 2 cylinder
• Mercury Mark 15, 2 cylinder
• Mercury Mark 20H, 2 cylinder

Straightway speed range: 55-60 mph

Minimum Age Req: 14

 

 

 

 

350cc Modified Hydroplane/Runabout (B Mod)

Displacement: 20 c.i.
Permitted engines:
• Swanson Champion-American Hot Rod, 20 c.i.
• Yamato Model 80, 2 cylinder
• Mercury Mark 20/25-20H, 2 cylinder
• Mercury KG7, 2 cylinder

Straightway speed range: 65-70 mph

Minimum Age Req: 16

 

 

 

 

400cc Modified Hydroplane (25 Mod)

Displacement: 22.0 & 22.1 c.i.
Permitted engines:
• Mercury 25SS racing powerhead
• Mercury 200, 22.0 c.i. powerhead, 1970 to date
• OMC 22.1 c.i. powerhead, 1970 to date

Straightway speed range: 65-70 mph

Minimum Age Req: 16

 

 

 

 

500cc Modified Hydroplane/Runabout (C Mod)

Displacement: 30 c.i.
Permitted engines:
• Mercury Mark 30H, 30 c.i. 4 cylinder
• Wizard WA25 30 c.i. 4 cylinder
• Yamato Model 102/302 24.5 c.i. 2 cylinder

Straightway speed range: 70-75 mph

Minimum Age Req: 16

 

 

 

 

750cc Modified Hydroplane/Runabout (D Mod)

Displacement: 44 c.i.
Permitted engines:
• Mercury Mark 55H c.i. 4 cylinder

Straightway speed range: 75-85 mph

Minimum Age Req: 16

 

 

 

 

850cc Modified Hydroplane/Runabout (Formula E)

Displacement: 49 c.i.
Permitted engines:
• Any motor manufactured as a service engine
• Any new motors must be reviewed by Modified 

  Outboard Technical Committee
• Any questions on legality of a motor please feel

  free to contact us

Straightway speed range: 85-100 mph

Minimum Age Req: 18

 

 

 

 

Stock classes

 

A Stock Hydroplane/Runabout

Displacement: 13.2 c.i.
Permitted engines:
• OMC 13.2 c.i., 2 cylinder
• Mercury “A” motor
• Sidewinder 15S

Straightway speed range: 55-60 mph

mim=nimum Age Req: 14 Years Old

 

 

 

 

B Stock Hydroplane

Permitted motors:
• Yamato Model 80, 2 cylinder
• Yamato Model 102/302, 2 cylinder with 7/16″ carburator restrictor plate

• Sidewinder 20S (probationary)

Straightway speed range:

Minimum Age Req: 15 Year Old

 

 

 

 

B Stock Runabout

Permitted motors:
• Mercury/25SS
• Mercury/Mariner 25XS without restrictor plate
• Hot Rod 20 CID
• Yamato Model 80, 2 cylinder
• Yamato Model 102/302, 2 cylinder with 9/16″ or 1/2″ carburator restrictor plate
• Sidewinder 20S (probationary)

Straightway speed range:

Minimum Age Req: 15 years Old

 

 

 

 

C Stock Hydroplane/Runabout

Permitted motors:
• Yamato Model 102 or 302

Straightway speed range:

Minimum Age Req: 16 Years Old

 

 

 

D Stock Hydroplane/Runabout

Permitted motors:
• Mercury Mark 55-H
• Mercury/Mariner 44XS

• 402XS
• Bass/Tohatsu

Straightway speed range:

Minimum Age Req: 18 Years Old