Mainstream has a log manifold that does excellent with turbo motors. Looks good too, not that it matters but it's a nice bonus. BTW, the aftermarket intake manifolds are designed to give you that added flow in the upper end of the RPM range. The plenum is bigger thus it holds more air, also the design of the runners makes a big difference on a turbo motor. Some engines like a long runner with a tapered velocity stack, some like a shorter w/ less taper. Talk to some of the UP guys and see what they've found they like, they should definately know about the turbo honda motors.