Mileage hit not as bad as I expected changing from 19's to 21's

[dk10438]

Pleasantly surprised that my efficiency is not that much worse going form 19 in to 21 in. Over 4000 miles I was averaging 364 wh/mi on the 19 in slipstreams with the 245/45/19 tires. With 1000 miles on the staggered 21's I'm getting 277 wh/mi wrapped with 245/35/21 and 285/30/21 Pilot Super Sports so they're about 4 percent less efficient.

 

[dcmackintosh]

364 is 31% greater than 277, that's an enormous change in the amount of energy used. How has your predicted range changed, or the battery percentage used to go 100 miles?

Edit: After reading your post again, it seems you're getting much higher efficiency with the new setup, is that correct? You probably meant 364 to 377, that would be about 4%.

Also consider the speeds. I would expect a larger hit at lower speeds, where rolling resistance is a higher percentage of the total drag. At highway speeds the aerodynamic drag will be much more significant than a relatively smaller increase in rolling resistance.

 

[dk10438]

Oops
364 v 377, was a typo