VVC BHP differential

[ccconn]

I am just about to pick up a 1.8 VVC with 150bhp
I see that the newer VVC engine outputs 160bhp
Can anyone tell me why this is so and is it easy to gain the extra 10 and more importantly will it be worth it?
Thanks

[ccconn]

Thanks a lot
That sounds the way to go
Where do I get the exhasut and any idea of cost?

[ccconn]

So chaps does that mean if I change the exhaust I will get a benefit? even if I cant change the ECU?