Thanks Belly.
There is some logic behind the madness. I had Martin do a power tune yesterday, after some fiddling the initial map was staggering, simply unbelievable. Very powerful, pulling like a horse and a quiet engine! But, and there is always a but

he wasn't happy with the smoke levels, so back to the drawing board. The finished article is great, a very different animal, but (I told you there's always a but

) we are now both curious to use the original map and by installing a waste bleed valve we may just be able to dial in a little bit more turbo run, allowing more air in and a cleaner burn. On his advice I have also today started using Millers Diesel additive.
Just for everyone's info 04 SWB 90 TDCI 77k miles
Info aside, anyone contemplating using Martin's services. You will not be disappointed.