Mechanical Cooling Fan broke during 6000 rpm burnout.

My Roadrunner used to pull the dang water pump shaft right out of the bearings and into the radiator at about that RPM with the steel 7 blade fan.
The first time it did it I chalked it up to a bad built water pump.
The second time it got replaced with a stainless flex fan.

On my current dart I have a 28 inch oversized radiator and a Jegs 16 inch, 2400 rpm electric S-blade with an adjustable temp controller for on/off range and absolutely love it.
Never ever goes over 210 degrees even in the AZ desert in town, and RPM's mean nothing to this setup.