1. The LS engine cooling system routes the inlet and outlet on the passenger side of the engine, which means that a radiator with the same hose orientation makes plumbing simpler. That's reason number one why I had Flex-A-Lite build a radiator for this truck. Reason number two was that the first long trip I take in the Parts Racer will be to Tennessee in August. Suffice to say that it's going to be hot as hell and I'll need all the cooling capacity I can get. One look at the stock radiator and you can see that not only is the new radiator substantially larger in capacity, but it's also a dual-pass arrangement because of where the inlet and outlet are placed.