Fastest 1/4 time I have at the strip is a 9.18 and that was above 90% SoC. I also turned a 9.92 at 21% SoC. If you wanted a very obtuse guesstimation, you could say 0.10 second loss per 10% SoC. But realistically, it's still turning 9.2's in the high 60% to low 70% SoC. I don't think 0-60 time is affected at all until you get in the sub-20% SoC range, because that's a traction issue, not a power issue.