Is 2:45 realisitc?

yes

"24 hour long run at 7:20" impressive!! watch out Yiannis Kouros!

Whoops. Meant 24 miles. Thanks for catching my mistake and answering in good faith!

Sounds realistic, how stress-free is your autumn going to be?

Yes

Id say yes for sure. I ran 2:46 with nothing on my calendar as hard as what you did save for a 22 @ 7:05 with 3-15 @ 6:40s. CIM is a fast course so you for sure should run with 2:45 pacer

Do they have 2:45 pace groups?

Your training would indicate 2:45 is possible, though probably at the limit of what's possible. Given that it's your first marathon, that does seem ambitious. I would still have 2:50 as your A goal and go out at 6:20 pace. If you feel great you can pick it up a bit after 10 miles but I would worry that if you're aiming for 2:45 you'll go out at 6:10 pace and that could easily lead to a blow-up.

Id assume they have a 2:45 pace group.
they had a 2:17 pace group.
its a big race so it seems likely

Very much possible, but in a range from 2:45 to 2:48 IMO. A lot depends on what happens on the day. Sub-2:50 should be a given. What's your weekly mileage?

Under 2:40 with lucky day

Your 1:18:30 half is roughly around a 1:34 for 25k. Double your 25k time then subtract 20 minutes to get a goal estimate for the marathon. So you double your 1:34 to get 3:08 subtract 20 minutes and you get 2:48. So you are real close.

The above estimate method worked for me three years consecutive I got within one minute of the predicted time each year. For me it was 1:26 plus change for 25k, the estimate using this method put me at 2:32 plus change and each year I ran 2:33

Caveat is that your H/M race and marathon have to be on somewhat similar courses, and cannot be radically different.

I would say go out right at 2:45 pace and just try and hold it. Good luck !

I wouldn't be comfortable aiming for 6:05/mile pace (not much slower than his HM pace) based on that training, but I'm conservative when it comes to the marathon

Weekly mileage has been hovering in high 60s/low 70s. Plan on pushing up to high 70s/low 80s until mid-november. I have generally been higher mileage (i.e. last training block was 60-65) for my speed.

I'd say 2:48ish depending how well you handle downhills. If you have not done much downhill work and your quads aren't extra strong, you may have late race issues.

Not to hijack this thread, but for anyone who gets a kick out of predicting marathon times:

- racing first marathon this weekend. Did a 1:22 high half marathon in March this year. Running ~40 miles per week this year, seemed to stop improving based on workouts soon after that half marathon. Two recent long workouts were 20 miles at 6:52 pace and 10 miles at 6:30 pace. Both were hard efforts. Did 1 other 20-mile run, and 5-6 runs building up to 20 miles from 15 or so.

Main goal for the weekend is sub 3, A goal would be 2:55.

If you're on the younger side and male, I would guess just under 3 with your mileage if you get good conditions. If you shoot for 2:54 it might get ugly.

Nah dude you're rolled. Start doping like Ruth or quit running

Low mileage

Stick with 3