Maserati GranTurismo Rear Diffuser Carbon FiberMDI Carbon Fiber Rear Diffuser for Maserati GranTurismo. All our carbon fiber Rear Diffuser are made with an Autoclave process, which uses the highest quality TORAYCA PREPREG carbon fiber fabric from Japan. More information on the manufacturers specifications: Finishes and Materials! Cures at 400 degrees and a pressure of 5Kg cm. One of the most advanced techniques for making composite components is by using PrePreg carbon fiber reinforcement, cured