can the z6 head hold 300-350 whp...it will have a port and polish...new valve springs, valves...and cam...will i need to change out the valve seat guides...or anything? if its best i do...how do i exactly remove and replace them?...may be a dumb question...but i prefer to know the correct way to do it

 

i'd be more worried about the block

 

block is already being built as we speak...i have already taken all necessary precautions...h-beam rods, turbo pistons, crank, etc

 

From what I've seen the Z6 head is good to about 380whp, but the Y8 head will flow more. With extensive porting, anything is possible - but your goal of 350ish whp is reachable. The block is more of a trouble spot. Rods and pistons help, but you might run into problems with the head not sealing and the sleeves moving around. IMHO, anything over 300ish whp - get it sleeved.

 

what am i looking at spending with gettin it sleeved?

 

There are LOTS of un-sleeved Z6s making upwards of 300whp.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EJProject &raquo;</TD></TR><TR><TD CLASS="quote">From what I've seen the Z6 head is good to about 380whp, but the Y8 head will flow more.</TD></TR></TABLE>

What?

 

You should talk to Rota92 as he has one of the fastest D series out there right now running mid 10s.

 

Stick with the Z6, you'll be fine! There are several 400+ hp Ds with totally stock heads w/o porting!

 

im stickin with the z6...but i just want the 300-350 range...can i achieve that with a mild port and polish...and some block guards...and so forth...or will i need to look more into some higher performance parts....its gonna be a daily driver as well...so its just gonna be during high boost on those nights filled with v8 racin...

 

im gonna try for the same thing with my z6 i would like to know how your project goes

 

the z6 head is capable of supporting your goals with enough work, including porting, polishing, good valve job, and enough boost.

 

ok with the valve job...i found the valves and springs i want to use...do i need to resplace the valve guides?...porting and polishing is taken care of...

 

whoever does the headwork should check the guides, and recommend replacement if needed.

 

should be easily done. i know a guy with a z6 head and it puts out 460 whp on 28 pounds of boost. worry about the block not the head.