Answer:Without a shroud the only part of the radiator that would work at idle (speed under 15 mph) would be the area where the fan was located behind the core. The shroud guarantees that air is pulled through the complete core, resulting in optimum performance.
Answer: You can use a fan shroud on the grill side, but it will not be as efficient since it blocks some air flow. The fan must be designed as a "pusher" instead of a "puller".
Answer: Sometimes a curved fan is better than a straight fan, but not always. Given the diameter of the motor hub, the outer diameter of the fans used on the typical race radiators curve for optimal design is minimal. Some straight blade fans will out perform curved designs.
Answer: Griffin's recommendation is to use an electric thermostat that senses bottom tank temperatures. The fan should be controlled to come on when either the A/C comes on or the coolant temperature exceeds a certain set point.
Answer: The CFM rating and amp draw depends on the fan. Typical CFM's for a 16-inch curved blade fan are 2070 and 2360 for a straight blade. Amp draw is 17.5 and 21.5.
Answer: Griffin does not recommend the use of a flex fan. If the flex fan is too close to the radiator the blades could flex forward causing damage to the core. If you are using a lower gear ratio fan, it can flatten out too fast at a lower speed and won't pull in as much air.
