A fan for traction.

[rockracer]

Interesting areo discussion.  https://youtu.be/L7imfnzF2Vo?si=a8Hgjox8G9D0JRni

[aircap]

Shades of Jim Hall and Shadow.

[71GSSDemon]

Agreed.  Jim Hall and Chapparel Cars.  There is some great video of their fan car from the 60's.  McMurtry Speirling is a modern version and has the world record at Goodwood Festival of Speed.

[John Burk]

Pete Robinson used a couple of suction devices to help traction . One used the engine blower for suction .

[TD]

The Chapparal 2J is on display in the Chapparal wing of the Petroleum Museum, in Midland, TX.  Not the easiest place to get to, kinda like Bonneville, but worth the trip if you are interested in the history of the Can-Am series and late-60s FIA sports car racing.

The 1978 Brabham BT46 F1 car was designed by Gordon Murray and driven by Niki Lauda and John Watson, the former winning the Swedish Grand Prix, the one and only time the car was raced.

Good stuff, except maybe if you are the driver behind 

[noboD]

As I recall the 2J used two snowmobile engines to pull the car down. But it would go 40 miles an hour which is the reason it was made illegal.

[rockracer]

Since we are on the subject of F1 cars, ect.  This popped up on YT.
Interesting, F1 car on the salt.  https://youtu.be/Fp0k7PKVNRc?si=czJf5F7fPnIz8Tqv

[TD]

Sorry for the thread drift.  That said, there's a really good overview of the 2J here:

https://automedia.revsinstitute.org/the-astonishing-chaparral-2j

The original Chapparal Cars shop, and adjacent Rattlesnake Raceway test track, is just a couple of miles south of the Museum on Texas Highway 349:

https://maps.app.goo.gl/D8FvwwkeKtejurt58

As I recall the 2J used two snowmobile engines to pull the car down. But it would go 40 miles an hour which is the reason it was made illegal.

[tortoise]

How about a sucker push car to get a streamliner quickly up to enough speed to get its own aero downforce working? Fun to watch, I'd bet. Or would it destroy the salt surface?

[aircap]

It's my understanding that most aerodynamics start working around 90, so what would be the point?

[noboD]

Thank you TD, that's more detail about the car then I have ever read before. The book Chevrolet Racing? is a good read if you can find it. I have my copy for about 50 years, may have to dig it out and reread it.

[tortoise]

It's my understanding that most aerodynamics start working around 90, so what would be the point?

Fan cars have full downforce at zero mph. With today's shorter courses, getting to speed in the shortest possible distance is necessary.

[noboD]

Wouldn't they be a problem on the salt?

[kiwi belly tank]

They suck & at best we have 3/4" of salt crust that's "kinda" stuck to the brine dirt on a good year so I don't think you'd make any friends sucking that $hit up & spitting it out the back of your car even if you did manage to sneak it through tech.
  Sid.

[aircap]

Hadn't even thought of that. El Mirage is already dusty enough!