Yes sir, looks like your right to me. My tires were 1.95", 100 / 27. After the post of 1.85" here I was thinking that too. Maybe it's just that motor, maybe it's my heavy throttle finger, I don't know.
Everyone is a little different on the throttle. That's kinda the danger with posting gear ratio's on the net. I usually run a tooth or two lower than what the pro's have on their setup sheets and will always start two teeth lower than any car instruction book says. I've seen to many beginners fry motors because someone said they should run a certain gear.
Just my $.02
Now where do you run your stock motors at? I'd really like to go to Cleveland this year and my son will run 12th scale stock if we do. We've never ran 12th scale stock here.