running lean -- plan of action?

[slow2]

... the leanness comes in @ boost and stays all way up and i get hesitence in 4th and 5th at high rpm -- 4K - 6K

Have you tried changing the FPR on your car.
If your FPR is old it may have become lazy, which you can get away with on part throttle/low-medium revs, but when positve boost comes on it cannot hold the correct fuel presure to match the boost.

Also check that the small vacuum hose that connects between the FPR and inlet
manifold is not kinked, blocked or split as this would cause there to be no rise in fuel
presure when you go into positive boost.

[Briggsy]

@chris and any others, after finally tracing back to a previous owner i also found out that my car had been fitted with a AMD chip. When i bought the car i was under the influence that it was totally standard, but a RR session proved me wrong. My figure's are the same as yours,267hp and 326ftlb, and also running lean but only on the redline so not much of a problem at the mo.
thought this might help.

[Chris5044]

thx 4 info