LRR tires

[Lazarus]

I found this website it's a year old but has lots of tire info. There's some good stuff in there if you want to wade through it.

The report reviews the technical literature and analyzes energy performance data from nearly 200 passenger tires on the market today. National fuel savings from improving the energy efficiency of passenger tires by 10 percent are quantified and the implications for consumer spending on tires, motor vehicle safety, and scrap tire generation are considered

That translates in to a 1-2% increase in FE.