Grille block example - manually adjustable from cabin
 

Found this over at Teamswift:

TeamSwift • View topic - Aerodynamic Foundation Vent

Member "vance" got the idea from looking at foundation vents (something I admit I'd never heard of - I've always lived in buildings with basements!).

Here's a manually adjustable foundation vent:

http://www.cookesupplies.com/product...entPlastic.jpg

And here are some images of what vance made on his car. Not sure, but you may need to log in to teamswift.net to see the full size attachments he posted:

Brackets installed...
http://ecomodder.com/forum/attachmen...1&d=1228868010

Rear of custom vent showing slider track...
http://ecomodder.com/forum/attachmen...1&d=1228868010

Installed....
http://ecomodder.com/forum/attachmen...1&d=1228868010

He's pretty happy with the results. You can read his full comments on the mod & its effects and see the bigger pics at teamswift.

Nice. I always wanted someone to do that... and it actually work! good job to them. :thumbup:

That can easily be recreated with almost any rigid material :)

I too have never heard of foundation vents.... I do live in Florida, however..

Too bad there are no pics of how the opening/closing mechanism is mounted to the vent and to the driver.

Basement vents are pretty popular in the southeastern states (Virginia, Georgia, Carolinas).

It's a manual choke cable, so it has a Z bend at one side, and (on a carb) it gets mounted to a hole in the choke cam, which to me, says it was mounted using some space age material in a futuristic method... or.. maybe he just left a raised tab on the vent plate to hook the Z-bend to?

Just a guess.

A manually adjusted grill block gives you the best of both worlds. The advantage of a complete grill block for faster warm up times and yet it allows you to open it up for increased cooling on hot summer days and for those slow speed hill climbs. It does needs to to be combined with some means of monitoring engine temps (Scanguage coolant temp, or radiator fan LED indicator) to let you get the best use from a manual grill block. The only thing better would be an automated griill block controller responding to coolant temps.

I've always envisioned something like this to use a cable mechanism like your gas pedal does to open and close the throttle plate. of course the pedal is a hand lever in the grille blocks case.

crawl-space ventilator
 

Had the designers of the vent had to design for houses that move at 100-km/h they would have discovered that their creation had about the highest aerodynamic resistance of any form they could have conceived of.The most basic fluids book would illustrate the extreme vena-contrata entry losses associated with a design like the one depicted.Better it remain on a home rather than a car. If you want to defeat the whole purpose of a grille-block,this would be the one to do.