Add 4 speed transmission for 15% gain in range on highway?

[TomT]

So, they are claiming an increase of 6% in efficiency... One assumes that this is probably optimized for their requirements so a street vehicle might not do quite as well, particularly if you factor in the different and varying driving conditions... Assuming 6 percent for sake of argument though, that would increase the range of the Leaf by about 4 1/2 miles. Considering the increased cost and complexity, I don't see a ROI there.

Some real world info, via ABG

 

[GRA]

So, they are claiming an increase of 6% in efficiency... One assumes that this is probably optimized for their requirements so a street vehicle might not do quite as well, particularly if you factor in the different and varying driving conditions... Assuming 6 percent for sake of argument though, that would increase the range of the Leaf by about 4 1/2 miles. Considering the increased cost and complexity, I don't see a ROI there.

Some real world info, via ABG

Yeah, it would be a tough argument. OTOH, this seems to have been a pretty quick and dirty conversion, so it's possible they could optimize it and get some more. It really just depends on the transmission/battery cost ratios, plus the effect on reliability/any extra maintenance costs. Since it was an alpine course I'd expect greater advantages in steady speed freeway cruising on flattish ground, but there's no info here to prove or disprove that.