Your engine sounds very similar to what mine is ( capacity & your intended power level ).I wasn't entertaining the use of 280's or 290's...but was thinking something along the lines of a 10.5 & 268 , since one of my old JUN's is now damaged.
You have now chucked a curve ball at me in regards to the cams I will go with ..so I eagerly await a proper figure once sorted from your test mule .
And I will be keeping the factory air box , but using a large carbon duct to the bottom of it that came off Geoff fear's gtr .