67 - 72 Chevy Mark VIII Fan install

There has been a lot of discussion on the internet about installing Mark VIII or Taurus fans in 67-72 Chevy Trucks. We've also been getting requests for Mark VII / Taurus fan Relay kits but up till now we haven't looked at it as a product.We decided to give it a good look and come up with a reliable 2 speed fan kit. Most are wiring them on at full speed and not using the low speed at all. I decided to see what this is all about. See more

Controlling a fan and water pump with PWM

Pulse width modulation allows us to do more precise control of electrical devices. In the racing segment Horse power is premium and PWM control helps keep Horse power where it's needed not on the engine running pumps and fans. With our Autocool R/T unit you can have the needed control for more precise cooling stability there by creating more HP and using less to power accessories. The R/T unit senses the retuning radiator water and adjusts the pump speed and fan speed for optimal cooling even at low speed driving, it will work with most all electric pump and most all electric fans up to 85 amps. Why is this important, if you run a boosted 502 in traffic heat builds quickly, with the R/T PWM it will ramp up the fan and pump speed to simulate highway speeds when your just crawling along. It also lets you cool down between runs at the track as if your at highway speed. Engines off but the pump and fan are running to cool it off. You can also turn off the fan and pump for a pass down the track and turn it back on at the end. Click here. to see the unit and pricing. For more info on PWM Click here

What Mark VIII style fan do I have?

To see how to test the fan click here