[Joel Koontz]

LouisianaGuy, I do not think you would get any benefit from creating a larger shroud. Getting the existing shroud to seal well would be more important. A larger shroud might actually be a negative as it would restrict more air when the fan is not running.

I have been running a Mark VIII fan for several years now and it seems to work fine with the existing fan shroud just covering part of the radiator on my 68. I have mine on a thermostat and going down the highway my fan virtually never runs at all. When it comes on while stopped it does not take long to cool down and cycle the fan off.

To seal mine to radiator I cut a slot down the side of some vacuum hose and used it as a cushion where it is up against the radiator.

Bigred455, I have read that running two relays is not the best arrangement. Better to use one relay of adequate size. If a relay is too small it will eventually fail reguardless of how many you use. Two does give you some redundancy which may delay having a breakdown, but from what I read, one of the relays will alway trigger slightly quicker than the other and for an instant take all of the load(load is by far the greatest at start up) causing it to eventually fail. Then your down to one and probably won't know it till the second one fails also.

I am using a 75 amp relay, but I forget right now the brand, or where I got them from. It seems to be working fine.


Sporter, I have also read that the Ford Solenoid is designed for short term intermitent use only and is not appropriate for continuous duty use as this would be.

After I installed mine I noticed some relays in a parts store that were intended for a snow plow. It specifically stated on the packaging that they were for continuous duty use. I have not tried them since mine is working fine but if I had to replace mine for some reason I think i would try one of these as they seemed to be heavy duty and had a high amp rating.

Please note the I am not tyring to claim that I am any type of electrical expert. I am just relaying what I have read in hopes it will help others. Before I installed mine I did a bunch of research. There is a lot of info on the Mark VIII and Windstar fans on the Chevelle Tech site and I would suggest doing a search there.