Reduce lift and drag on fastback cars (and toppers)
 

Reduce lift and drag on fastback cars, and the approach is likely to work on SUV toppers too.

https://www.youtube.com/watch?v=niFYzjZAFhk

Thank you for another great video Julian. Now I wish I had requested that you do more testing of the Skoda Roomster before it went to it’s new home. I have a Golf TDI and I feel I have optimized aero everywhere except the back. I wonder if there are some gains to be had there? I have your book, but from page 134 it seems that your results from the roof extension mpg improvements were somewhat inconclusive.

Well, I didn't want to make silly claims as to precise mpg improvements, as you so often see people do. I am pretty confident it worked.

I meant to ask, what is meant by SUV “toppers”? Here in some parts of the U.S. a “topper” is an aftermarket shell that covers the bed of a pickup at the same height as the cab.

(Edited for clarity) And an SUV does not have an open bed like what we call a “Pickup Truck” here in the US. I believe I have heard the vehicles in your next post referred to as a “Ute” in Australian English usage? Or it that reserved for the unibody pickups like the Chevy El Camino?

Actually here in Australia they're called 'canopies'.

I meant that the approach taken in the video could, I would think, be used to reduce drag and lift on people modifying their trucks like this:

http://ecomodder.com/blog/wp-content...ge-aerolid.jpg

I've always wondered why the NASCAR Camping World race trucks don't have an aerocap instead of those big spoilers.

https://s3.amazonaws.com/speedsport-...88-300x180.jpg
https://s3.amazonaws.com/speedsport-...88-300x180.jpg

You'd think Camping World could sell a few race-inspired canopies. :confused:

why
 

They don't reflect the body templates NASCAR uses to qualify vehicles for competition.
Only Cybertruck would have anything approaching such a shape.

Race on Sunday, sell on Monday. Here in America we love big tough looking pickup trucks.

Regarding race trucks: might be the rules trace back to amateur truck racing in Bakersfield at Famoso, in the '80's whereby the truck had to remain a truck, no aero, because the truck went to work Monday in the oil fields.