If it helps, here are the number 1 & 2 times for our combination:
11.52 120.28
11.58 117.98
Both were 511ci. I know for sure the second had a solid roller; pretty sure the first did also but, can't confirm.
So, with your plan to go to 499ci and a solid roller, I'd say you can potentially pick up around .3 once everything is sorted out and you've practiced, tested and practiced some more.