Rear diffuser
After numerous photoshops, sketches and cardboard engineering I settled on a multi fin design with large vortex centre fins. I kept the angle at a range so flow wouldn't separate, and designed it to work with the rear angles of the car and the exhaust for a one-off design. I finished the design in aluminium and HDPE with a blow over in black. Its securely fastened to the underside of the car using a number of bolts and metal brackets.