2011 250ec/300 cylinder swap

[smccoll]

Hey guy, i have a 2011 ec 250, i would like a little ore bottom end out of it,i was thinking of putting a 300 jug on it.
Here are my questions
1 will the 250 head work with the 300 cyl.
2 is there a better(cheaper) way of getting bottom end torque out of this bike , i just pit a piston and rings in it last year.
i guess what iam looking for is a little more bottom end , my dad rides this bike now and he rides a little slower but still wants some bottom end grunt !!! thanks in advance guys