306 dturbo with 2.0 hdi conrods

[Niall]

That's because no one has ever gonna internal and upgraded most things major of things to be done is pumps injectors and clutch and turbo, to see past the 250 mark you need to go more in depth with things and lighten replace and over size lol

Clearly you have never seen Darrens thread then

But fair play. If you can make that sort of power, i would be impressed and i hope you do manage it because it will embarrass a lot of things out there though!
As Silverzx says though, imo 250bhp is enough for a 306. Ive seen 306s with 450bhp and they can't use any of the power at all.