2013 Topless Modified Rules

Body

• Dimensions 76” wide, maximum 36” tall, minimum spoiler 12”. Only 2 outer-side panels, must match spoiler, minimum 30” length, maximum 36” length. Side Panels must be braced.
• No Tops
• No Front Fenders
• Nose maximum 48” wide
• Safety Netting may be used on top hoop

Block

• OEM Steel Block

Crank

• Minimum 49.5lbs with key ,gear and pilot bushing

Rods

• Any Steel rod. Flat top pistons, ZERO deck,plus or minus .003 tolerance

Heads

• Steel Gm. 23 Degree as casted. Angle milling allowed. 2 degree max. Any Head must be between 23 – 21 degree . NO Tolerance
• No Raise Runner heads.
• 200cc casted head. max port rule, no porting, cannot measure over 210cc. No Tolerance
• Any Cylinder Head measuring over 215cc must carry 50lb weight penalty.
• 2.02 Intake: 1.60 Exhaust: 11/32 stem: No Titanium

Cam

• Any Cam: max.525lift or GM Part #24502476. No Rollers: .003 tolerance,hot at the valve.

Carburetor

• Any one(1) four barrel carburetor

Ignition

• Any ignition allowed

Shocks

• No Adjustable gas or external reservoir shocks

Wheels

• Steel 10” Max

Tires

• Right Rear must punch 50

Weight

• 362 max Cubic inch : #2400: must add 50# for heads over 215cc
• 604 Crate :#2300
• 602 Crate :#2200