Just failed emmisions on a busa engine with cat. If i turn the fuel pressure down the co levels drop but the lambda rises,the manifold is blowing from behind the end can could this be the problem??

Mine failed for Lambda too (blade) - what I've been told is that since it's a measurement of unburnt Oxygen in the exhaust gasses and any leak in the exhaust system will give a false reading. False high I think.
Get the hole sorted and check it again.
Good luck.

Retest tomorrow have taped and pasted everything up so fingers crossed.I have lowered the pressure down to give me a co level of 0.15.

failed again on lambda this time

Its fuel injection so i have been adjusting the fuel pressure and trying to balance it. I have booked it in a mates garage for an hours messing round with the analyser.
Hows the gt2 body going anyway mate coz thats next winters project by the look of things(if i ever get this bag o s**te through the emmisions)

I don't know if this is any help to you or not, but I know most of the folks with Blackbirds (also injection) use Power Commanders to map the ignition to allow them to pass the SVA emmisions.

Third time lucky.....Passed

just in time for summer