Ducted Radiator

[Tygen1]

For years I've been driving around with my grill 100% blocked. I finally got tired of replacing radiator fans because of it constantly turning on and off so, I cut a hole in my grill block. My transmission cooler was not very effective either, so I upsized it also. I used some coroplast "surplus" signs to make my ducting. It is just jamed in there. I made the duct as wide as the trans cooler and radiator even though the grill block hole is much smaller, just as wide as the licensce plate, just in case I want to block it again.
The results are great. The fan has only turned on in stop and go traffic and the temps stay under 210 on the highway. The trans temp is way lower because it now has significant air flow and a three times larger cooler. On the down side, it takes waaaay longer to warm up. It would be nice to have an on the fly grill block.
It seems like it has helped the instant mpg numbers slightly, but if it did help, it is very small.

[busypaws]

You said "ducted" that got me thinking... How about a furnace vent used on forced air furnace in a home (12x8 inches, couldn't be more then $10 dollars at Home Depot) They have levers on them to open and close. Run a cable next to the hood release cable then you can open/close the vent from the drivers seat.

[graydonengineering]

Originally Posted by busypaws

You said "ducted" that got me thinking... How about a furnace vent used on forced air furnace in a home (12x8 inches, couldn't be more then $10 dollars at Home Depot) They have levers on them to open and close. Run a cable next to the hood release cable then you can open/close the vent from the drivers seat.

Yes, only problem is, the luvers will give a fair amount of restriction requireing a larger opening for the same cooling effect. That would be a fast simple solution though.

You could also make a single paddle on a horizontal shaft actuatated by a cable exactly like a throttle body. When in the horizontal "wide open" position, it would cause very little restriction.

[Tygen1]

It was around 107 today with 60% Humidity. The Duct worked great. I'd say it performs as well as not having grill block at all! The fan never kicked on while on the highway and kept temps around 215, which is just right

[Weather Spotter]

take a look at my lower grill block page, I have used two forced air grates to block and remotely open the lower grill.