The chassis is tubular steel, both square and round, depending on functionality. The chassis is an engineered unit that favors rigidity and lightness through cleaver triangulation. A number of safety features are an integral part of the chassis: double roll bars in the cowling, double roll bars over the 25-gallon fuel tank located behind the passenger seats, impact bars in the doors and two seamless dome-35 steel (FIA-approved) roll bars that are gusseted into the chassis. This provides a full perimeter of protection for the occupants. Steel floor, steel sleeve over the drive shaft and heavy metal yokes over the drive shaft universal joints provide additional protection. The fuel tank is stainless steel with a submersed fuel pump to ensure reliability even when the MkIII is taken out of long-term storage. Baffles are integrated inside the tank to eliminate fuel displacement when high g-forces are at play.
The Allard J2X MkIII’s front aluminum grill is protected by a tubular steel bumper that, like the rear ‘nerf bars’, has a 5-mph impact resistance.