U-Build GT-40

  • U-Build GT-40: Tomy Mega-G short-wheelbase platform
SKU: 1016 Categories: ,


U-Build GT-40

Based on the Tomy Mega-G short-wheelbase platform, this car utilizes the Tomy GT-40 hard body, which is a very detailed hard plastic body that you can purchase un-painted or factory painted in popular GT-40 era livery.

Class Rules:

Body: Any color Tomy GT40 hard body. May be lowered and otherwise modified but must retain all body features, windscreens and rear panel. Trimming to clear track and rail may be necessary. Interior is not necessary. *Bodies are excluded from width requirements below (as they may not fit within this dimension).

Chassis: Stock Mega G Tomy chassis. No modifications allowed except to straighten chassis and peen axle holes as necessary. You may open shoe spring box for secondary electrical path. The front axle holes may be reamed to .052”. Peening is allowed.

Armature: Arm must measure 6 ohms or higher. May use any brand hot stock 6 ohm arms.

Electrical: Any brand shoes, shoe springs, motor springs, motor brushes. Must use stock brush tubes (no big foot or set screw types). OK to use Tragni Tune secondary electrical path.

Magnets: Stock motor and traction magnets. Magnet orientation must be stock (measure no greater than 10 grams of force on VRP downforce meter).

Guide: Only one guide pin is permitted. Any brand guide pin may be used.
Gearing: Stock gear ratio (7/25) but may use whatever brand plastic gears you prefer.

Wheels and Axles: Any brand, type, material or size front and rear wheels and axles.

Rear Tires: Must use slip-on silicone (recommend Blue “Super Tire” brand, compound “A”). Dual compound sponge-silicone tires are not allowed.


    1. Races shall be run at 15.0 volts +/- .25 volts.
    2. Note that the rail typically measures 0.015 tall around HSRW. SJSW rail height is 0.013.
    3. No component on car may measure more than 1.312 wide (wheels, chassis, body*, etc.).
    4. If a component rule is in question then use the stock O.E.M. component(s).
    5. Final interpretation is with the race director.

Additional information

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