Dr.Jass
Pastor of Muppets
With aluminum blades, it's a flex fan... unless they're like 1/16" or more thick. The Hayden is still your best option, but you've been poisoned by the stupidity of other racers who bought cheap shit and it didn't work for them. If you know how to correctly configure a shroud, you could get away with a 4-blade fan... but few people know how to do that.