Shoukd easily run 10's. Have u track logged?? My best has been 10.7@133 with a 1.79 60 on the stock converter gears drive shaft on stock suspension except bmr springs and steeda lcas, and on 19's front 18" nittos rear 93 pump gas too. On the converter I got the 60 to 1.53 on same mods only adding stall but it's knocking up top and dropping timing quite a bit so it only went 10.5@129. Also on stock gears btw.
Are you shifting into 4th OP?
I'd contact Mike Rousch. He is the best 6R80 tuner out there period!
However, you'd be killing it with a convertor! Best thing I've done to my car hands down.