Training Speed vs. Taper Speed

I will let the experts weigh in, but I am pretty sure the pace difference is not due to tapering (unless you screw up a taper).

My training pace is about 9:30-10:30.  Race pace (oly race) is high 8s.

This is not an easy question to answer, as most people's training paces will vary based on the type of run.

For my last marathon, I was running around 8+ for easy runs, and ran a 3:11.

I know people who run 2:45 or faster for the marathon, and they have runs that are at my easy pace.

As mentioned, it really has nothing to do with the taper (other than making sure you are rested and ready to go on race day).  It has to do with overall training loads and various paces during workouts.

The person who runs 100 miles a week at 8-ish pace is going to much much more fit and prepared to run in a long distance race than the one who only does 20 miles a week at 7-ish pace.

My typical training pace and racing pace are not close at all. I qualified for Boston last year and the vast majority of my training runs were 60-90 seconds per mile slower than I ran in the race. My training paces remain in the same range regardless of the race, so for short distance races I'll be over 2 minutes per mile faster.

To get fast you have to run fast, but not very much in relation to overall volume.

Caveat to that ^^^^^^ (McMillan charts)

You should put in your MOST RECENT race time.  If you are using a 5k PR from a year ago but since then have not run as much and have a slower current 5k time (generic example), then you are doing yourself a dis-service.