So I did some testing today and there seems to be no measureable difference between the two types of wheelcovers
It was a nice windless day today so I did some level ground and downhill coastdowns and both types performed exactly the same. Both were very slightly better than plain 15" steel disc but I dodn't notice any difference the two types of covers.
I guess difference must be so small, that it is not possible to "measure" it by our crude methods
I also had an alignment done today and I must say that I'm very disappointed with the result.
I have done some research on toe and camber and their effect on rolling resistance and decided to go for 0 camber and 0 toe on the front axle and 1 degree camber with 2mm total toe at the rear.
Before alignment there was 0.5 degree camber and 2mm total toe on front axle and the rear was all over the place.
But after an alignment was done, car now coasts worse than before
How is that possible?
I thought that 0 camber and 0 toe was supposed to be the best setting but it doesn't seem to be the case on my car.