fingerbone said..
wont the propeller make the car go backwards?
Nope, engine and airscrew rotate anti-clockwise, [when standing behind the VW]
Why should it overheat?
The cylinders are still getting airflow over them.[on the bonneville flats it should be rolling along at a good speed too.]
This engine has a ruddy great oil cooler as well- remember, it came out of a tank and not an aircraft.
The VW is yet to have its rollcage, safety gear, nitrous oxide and modified drivers seat fitted [needs more room for the drivers nuts]
It runs on propane too- so its kind of environmentally friendly.

The bloke that cobbled it together has 5 or 6 similar radial engines in the front yard of his home that he loves to fire up!
Thats what I call an effective way of beating the neighbours leaf blower.
I dont think he is married for some reason.......
I dont have the link- but if you google "radial engine VW" it will be top of the list.
stephen