Now SM legal effective the Feb 2018 GCR.
Due to the design of the factory differential housing there have been differential housing failures causing DNF’s. The factory differential housing has a notch built into the casting on the passenger side arm. The intent is to give the differential a breaking or failure point in an accident so as not to damage more of the drivetrain. This notch becomes problematic in the race car world as often subtle or mild bump drafting can cause that notch to perform as Mazda intended it and fail. Once that fails, the ear breaks off and you no longer have the ability to continue.
We have designed a 2 piece aluminum solution to be welded onto the rear differential housing to strengthen it for racing applications. Made from 3/16” thick aluminum and laser cut for a precise fit. With our solution we do not require any grinding of the differential housing and provide 2 separate plates.
The large plate welds onto the back of the cavity on the differential housing and the smaller plate welds on the top of the differential housing. We believe that welding only the large plate on is not enough and an additional plate is really required for the utmost in strength giving you additional reinforcement in multiple planes.
a. Reinforcement of the differential housing ears is allowed for the purpose of repairing or reducing breakage at the factory stress riser “notch”.