Agreed….Flex fuel street vehicles will run E10 or less to E85 without any problem. The ECU mapping/ control corrects for any blend from low to high.
In drag racing competition where fastest or most consistent is the goal, any difference in ethanol blend percentage from desired E85 can possibly be noticeable. Most I know racing with E85 (and they are all using carbs) and purchasing at the pump, will test prior.
Like was stated in the video, oxygenated fuel made the most HP.
Most serious E85 racers I know don't use pump E85, they use ignite E85 so the content question isn't an issue.
I use E85 but the tune is closer to an e65-70 tune due to the inconsistency of E85.
Most of those same people also use an NGuage to switch maps so they can drive home after burning through a tank of ignite.
E85 in a street car not built with taking advantage of E85 in mind doesn't really yield much anyway.
My car only picked up 20 wheel hp switching to e85, my dynamic compression is about 9.1. you need to be in the 9.6 to 10s and above for E85 to be if any real benefits E85 helps with BMEP which is what causes knock.
The expense of E85 on a 10-11 SCR engine is not worth the gains IMO.
I'm moving to ID 1000's just to get the duty cycle down on an e tune and thats $1200 alone