I have heard over and over that the D15B vtec and D16Z6 vtec heads are interchangeable, but is there any differences, like in valve size, port size, or combustion chamber size? I know about the lack of Purge valve, but otherwise. . .
I plan to put a D15B head on a refreshed D16Z6 bottom and wonder if my compression ratio will be affected by a combustion chamber that could be different size or shape.

I haven't gotten the head off yet to visually compare. In fact, I haven't pulled the D16Z6 thats going bad out of the car yet. Wednesday it comes out and D15B goes in.

Sorry if it's a repost and thanks for the help.

 

bump?

 

I think the D15B has a more agressive cam...but I'm not sure about the combusion chamber or the valves...I think they flow the same(I heard the D15B is the JDM Z6). Someone on here is sure to know...but try checking D-series.org.

 

as far as valve size goes, jdm d15b uses the same size valves as the z6. the d15b also does have a more agressive cam than the z6 cam. comparable to a zex cam actually. compression with a d15b head on a z6 bottom end should yield 9.4-9.6 if everything is stock and depending on size of head gasket

 

Thats awesome and I do appreciate it.
Stock D16Z6 is 9.2:1 correct? . . . so if I were to use the D16A1 pistons. . . maybe that'd be too high-compression to run untuned. Comments?
B

 

identical heads and the d15b has a more aggresive cam

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gold_ef &raquo;</TD></TR><TR><TD CLASS="quote">identical heads and the d15b has a more aggresive cam</TD></TR></TABLE>

 

same p08 head casting...

but there has been plenty of debate on the cam... i swore that the two were different for years, but somebody on d16turbo a while back measured it out and proved they were the same. not sure how credible it is but here was our argument...

https://honda-tech.com/zerothread?id=692065

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99CivicSiBrian &raquo;</TD></TR><TR><TD CLASS="quote">Thats awesome and I do appreciate it.
Stock D16Z6 is 9.2:1 correct? . . . so if I were to use the D16A1 pistons. . . maybe that'd be too high-compression to run untuned. Comments?
B</TD></TR></TABLE>

I don't know what cr you would have with those pistons...but unless you are using some other power adder...just use higher octane.