I read that the standard vr engine is good for 300bhp, any truth in this?
Good for 300 BHP how?
N/A you'd be very lucky to get 300 BHP - even with wild cams, big valves and seriuous headwork, I think 300 BHP is out of reach...and if you could, it would be so non-standard that you could hardly call it 'standard.
Forced induction?
I guess so...with a decent IC, bigger injectors, a small pully on a VF S/charger...then I suppose 300 BHP is achievable on standard internals.