6 port BP manifold, yes... really.

[NoDOHC]

I don't see why you couldn't use the stock ECU, it uses the air flow meter to determine fueling - this should compensate for any differences in the VE seamlessly.

The big issue that I see is the ignition. The factory ignition is notoriously weak at high revs (25% of idle ignition energy at 9,000 rpm). This means that you probably won't make any power past 7500 rpm anyway, regardless of how much air and fuel your engine can breathe.

Still, the manifold development is a good idea. The factory intake uses the elbow and intake piping as a plenum for the secondaries. I think I would put a plenum in for the primaries, you will be using them with the throttle mostly closed, which will exclude the use of the intake piping as a plenum.

This is a cool idea. I wish you the best of luck.

I wish you had posted this in the engine tech section, as it really isn't as much a generation specific question as an engine question.