so is it two throttle bodys with custom intake manifold also sounds like a turbo but thats just me sounds nice all the sameStock cams will flow up to 6500 redline, but its the lower intake manifold that restricts flow above 5500. Anything higher needs lextreme regrinds or kelford billets with stiffer springs but thats really it.
Regarding the oil flow issue, you can tap 1/2" oil return lines from the rear cam plugs at the back of each cam cover. By doing this, you'll allow the oil to dain effectively. When my had my 1st UZ, it burned a small amount of oil and I would see my low oil light appear on the freeway and all I had to do was lay off 500rpm or so and the light disappeared... allowing the oil to drain from the heads.
Here's a vvti UZ revving to 9200rpm:
He's got ITB's w/ dual plenums and at 407bhp, it matches an LS1 and is knocking on the 5.0 coyote's back door.
run a stand alone, change cams, port heads and change inlet it you want to make efficient power over 6000rpm