i have a 62mm off a JDM Integra Type R the only thing u have to do is open up a couple of holes a bit on the intake manifold.

 

Dyno tested EB Performer X manifold bolted on a Y8 netted over 5hp increase.. while its small amount its still a gain for a reasonable small cost IMO. port matched TB i think would give a slightly bigger gain onto that as well..

 

I'll break down intake manifolds as I know them:

Long runners- good low-midrange, poor high.
Short runners- the opposite.
Large TB- good top end, less low-mid.
Small TB- the opposite.
Large plenum- better top end, less low-mid.
Small plenum- the opposite.

Overall, I think building for a better top end is more forgiving than building strictly for midrange. I think the midrange loses are minimal with a well flowing high end set up, while building strictly for midrange becomes very if not completely limiting at about 5-6k rpm. Imo, the best set up on a D-series for the money is a Y8 manifold with TB bored to 60mm/or 60mm B-series TB. (The Y8 has shorter runners and a larger plenum than the Z6.) I haven't tested this set up yet to be sure, but that's what I'll be trying.