d-series are limited to around 400 on the average build like mine. they make power just fine and are way cheaper.
my setup consists of
d16z6
Eagle rods
wiseco pistons
Arp headstuds
cometic .051 MLS headgasket
crower valvesprings and retainers
stock cam
y8 intake manifold
competition 7lbs flywheel
competition prostreet clutch
z6 trans(needs an obx lsd)
Silly Sohc equal length AC compatible ramhorn manifold.
3" DP with electronic cutout
turbonetics .63 .60
TiAL 50mm BOV
TiAL 38mm wastegate.
its really all in the tuning and the way you drive it if it will last. mine is lasting just fine. Still runs right now, but i pulled everything back out of my car to clean up the engine bay a little.