Full-Race 4.5″ Dual Back Door Race IntercoolerFull Race 4. 5 Dual Back Door Race Intercooler Full Race designed this intercooler for high boost high power drag racing applications. Originally intended for use on Honda Drag builds, our customers such as Pepe Loco have gone deep into the 6s with it (1 4 mile) Available in dual backdoor or single backdoor configurations with 3 inlet and 3 outlet. Application Notes: Dual backdoor setups requires center mounting the radiator on most applications