your right, those two cams along with the cam bisi makes, makes power hands down. like i wrote before, most aftermarket cams (crower, gude, etc) will not make better power over the stock cam. i.e. usable power though out the power band, no drop off at 7,200. mind you, i am refering to a stock valvetrain head. so nothing bigger then a stg.2 cam.

in the end anything you add to a d-series head will be a waste. expecially considering you can build 400 whp with a piston/rod swap and a t3/t04e (of course some 780cc & 20+ psi will help also). why mess with it? save the money for something else, like paying Matt for a tune.

why are you going to take it up that high?

 

So you would recomend building the bottom end vice building the top?

 

its really up to you. but of the members (rocking the d-series) on H-T, D-series.org, Turbod16.com; most have these items or "better". not saying its the formula for a "400 whp" d-series, but it is very close.

780cc injectors
8.5-9.0:1 CR
h-beam rods
t3/t04e 57 trim turbo
cast manifold
~28x10x3 intercooler
tial wg & bov
arp headstuds
z6/y8 headgasket
boost controller (able to adjust to ~25*)
many hours of tuning
stock otherwise

however the +500 whp d-series club has more requirments, like agressive porting or the head. so again its really up to you with how much power your going to be shooting for. but don't be surprised if you shoot for 500 and fall short.