There is only one reason GM didn't race the Volt up Pike's Peak. It can't do it on electricity all the way up. I think they should have done it anyway, but I understand why for marketing reasons they didn't want the press hounding them over the fact that they couldn't race 12.42 miles on a car that is supposed to do 40 miles electric.
Wired reported that "Nissan tells us the state of charge meter showed three bars (out of 12) remaining at the end of the run. That suggests Hord burned through three-quarters of the 24 kilowatt-hour pack’s capacity during the run."
That suggests the Leaf burned through 18 kwh going up. Assuming a 100% charge and not the 80% charge Nissan recommends for daily driving. Well beyond the range of the usable 8kwh of the Volts 16 kwh pack.
Still I think GM would have been smart to do it, because undoubtedly the Volt would have smoked the Leaf's time, and any gas used would have been less than 1 gallon, and demonstrated the Volt's range extension capability under arduous race conditions.
http://www.wired.com/autopia/2011/06/ni ... ikes-peak/