125bhp is what a stock healthy 1.8 should show at the wheels. A williams should be around 130 ish at the wheels.
Also all the williams put out over the book figure, hmm didnt this you knwo seem odd, liek the rolling road in fact is talkign sh*te, but why woudl anyone say that after all a RR is gospel. They can never be faulted I mean of course 1 litre OHV novas have 100bhp at the fly but 30bhp at the wheels, a 70bhp tranny loss is normal asint it.