[piecesparts]

Everyone has an opinion and here is mine. I got it from the discussions that I had with first the "Flexilite" people and second the people from "Be-Cool". You meet some really great people on a Hotrod Power Tour. The pusher fans provide two downfalls--1st) they restrict air flow by being on the front of the radiator. 2nd) they are somewhat inefficient on the fact that in most cases they are up against the radiator and they push air in only the small area that they cover and a lot of that is diffused against the fins and dissapated on the outside of the radiaotr rather than going through it.
The puller fans if mounted right will move more air, give a better flow through the core fins, and provide a better movement of air in the engine compartment. Now comes the decision on what fan to get. There are a lot of them out there on the market and some move some great amounts of air and some are just there to take your money. If you are driving on the highway, then in most cases any fan will do, but if you are going to load up the truck and work in a hot city, then a better grade of fan is needed. I finally settled on the dual 11" fans from SPAL because each fan is rated to move around 2800 CFM of air against a dynamic load. (Dynamic is something such as an engine compartment that has other thnigs happening rather than just an open space). A lot of fans ar tested in a "Static" conditon which is to measure the air flow across from point 'A' to point 'B' which has no backpressure in it. The sales people will tell you that their fan is limited to certain levels of Horsepower With or without A/C on. SPAL dosen't do that. I am running my fans in two different trucks and I can run on a really hot day and have no problems with them. They sound like gas turbine engines up front, but it works well. My setups are designed to run one fan at slow speed, then speed up as the temp goes up, and finally the second fan starts if it is really hot or the A/C is on. I have not gotten to the second fan point yet. I recommend some phone calls to Be-Cool and Flexilite and then do comparisons before doing a lot of work and then just bolting something on. I have seen a lot of really nice Streetrods sitting on the side of the road with water boiling out of them. Imagine putting $5000 in a motor and putting a $19.95 fan on the radiator. NOT ME.