When we were young, our parents had us all (mostly) potty trained by 2.
I don't know a single adult in their mid 20's on up who wasn't potty trained by the time they were at the very least 2 1/2. My husband and all 4 of his sibling were potty trained by 18 months.
Now, the parenting method has changed in our time and most people wait longer until the child exhibits all of the readiness signs. (Myself included, my almost 4 year old still isn't totally potty trained, so I am working on my 2 kids at the same time as well!)
In any case, I think if you work extra hard, put the boys on schedules (take them to sit on the potty ever 20 mins- set a timer) and put them in big boy underwear or no clothing at all... it will really help.
Lots of great resources exist out there. Good luck!