Chassis

Two-wheel drive to front or rear wheels or four-wheel drive is allowed. Chassis must have independent suspension on all four wheels. Each driven wheel must have a flexible joint, eg: dog bone/s or universal joint/s in its driveshaft. Drive train and suspension design is free from restriction. Flat Pan (1/12th and 1/10th Track Style) chassis are not allowed. The Chassis must not be shaped to gain an aerodynamic advantage. In principle the underside of the chassis must be flat and parallel to the ground along the entire length of the body-shell. Aerodynamic shaped parts (splitters/diffusers/tunnels/etc) may not be fitted to the chassis.

Motor

Any ROAR or BRCA approved motor. All brushless motors for the Stock class will be wind rating of 21.5 turns, clearly indicated by the manufacture on the external casing. Stator, Stock Motor: Only three slot “Y” wound stators are permitted. No delta wound or slot less stators are allowed. Only circular (round) pure copper magnet wire permitted. The three slotted stator must be wound with 21.5 turns of 2 strands of a maximum diameter of 0.0724 mm per slot.
OR
Tamiya 540J or RS540SH (2 Slot) silver can Johnson / Mabuchi standard standard replacement end bell motor. Tamiya’s part N0 #53689. Silver cans must not be modified or tampered with in any way.

ESC

Speed Controllers as per ROAR BRCA list. Speed controllers eligible for Stock classes must provide zero timing advance, along with disabling advanced motor control functions (i.e. Boost, Cheat Mode, Turbo, etc). When the “0 Boost” profile is enabled, it shall be indicated by a blinking LED while the ESC is armed and in neutral position.

Body Shell

Any pre 1990 model, 2 door or 4 door road / race car. Deck lids and spoilers that come out with the car are allowed. No additional skirts, raised/extended wings or air controlled surfaces are permitted. Body must be trimmed to trim lines. Full rear bumpers required. If unsure check before racing. Bodies considered outside the spirit of the sport can be excluded without notice.

Tyres

HPI tyre part No #4793 (Front) and #4797 (rear), using stock tyre insert provided with the tyre. Any HPI wheels designed to fit these tyres. Wheels and tyres designated as “Front” must be used as front tyres/wheels, “Rear” wheels/tyres must be used as rears. Some tyre tread must be visible. Grinding of tyre is not permitted. Tyre traction compounds and tyre warmers are not permitted, No altering, changing or softening of tyre is allowed.

Hop Ups

Any Hop Ups that are available from the Manufacturer

Batteries

Any 2 cell Hard-cased approved 7.4 Lipo packs as listed on the ROAR or EFRA websites.

Gearing

Gearing is not restricted.

Weight

Minimum 1450 grams ready to run including transponder.