One of the only weak points on the 964 and 993 chassis is the engine carrier. When these models are tracked, or are fitted with stiffer than stock engine mounts, the engine carrier should be reinforced. If it is not, the carrier is known to bend, crack, or even break cleanly away from an engine mount in response to increased vibration and stress. The Porsche factory was aware of this problem and equipped its race cars with a reinforced engine carrier. Rennline now exclusively offers an engine mount reinforcement gusset kit that can be welded to the engine carrier by your shop.