4.5" Grand National rules

 Motor: ProSlot 16d or S16d,  Parma 16d or S16d, and older style 16d motors with approval.

(Chinese arm motors only)

Chassis: 4.5” Flexi Steel chassis. Aluminum pan allowed.

Gear/axle: May run 1/8 or 3/32 axle and 48 pitch or 64 pitch gears. Gears may be any ratio. Plastic spur gears only.

Tires: Must run front tire with .500 min diameter and .375 min width. May run any available rear tire. Foam tires only.

Chassis must clear .047 tech gauge.

Body: 4.5” Midsize Grand National bodies from the 50’s,60’s,70’s. American manufactured cars only.

Cars without a rear spoiler may add a ¼” spoiler on rear.