The 99-00 b20b is rated 9.6:1 C/R. 146 hp and 133 ft-lbs torque. What would the compression be with the P8R head(honda orthia head) on a 99-00 spec b20b? What headgasket would you use? An Ls headgasket(81mm combustion chambers) would'nt match up with the p8r 84mm combustion chambers. Supposedly the p8r heads flow almost as good as the vtec heads due to the 33mm intake valves and bigger 84mm combustion chambers. What size are the exhaust valves? 28mm? Also are the b20b 99-00 spec oem cams an upgrade in the p8r head?
I've searched honda-tech but not much info. I guess its not a desirable setup.
Sorry with all the questions im just curious.

use the p8r headgasket for 84mm it really doesnt change much the comb chamber is a littlelarger so youll lose some comp. but they run strong.

What pistons are in the B20B youre planning on using? PHK's or P3F's?

I have the 9.6 comp b20b.

NOPE YOUR WRONG! You will most def gain compression so my compression would be 10.1, if you have the 9.6 c/r b20b.

I just bought a P8R head for $80. YAY! Could i use skunk2 vtec valve springs and ti retainers? Could i use some ITR valves since the p8r has the same size valves? Im gonna get a skunk2 intake mani and skunk2 66mm throttle body also and go boost. BUMP FOR SOME INFO!!!

Why would you GAIN compression when going to a head with a bigger combustion chamber? What is your logic here, and why bother asking if you are going to disagree with the only person to give you the right answer? Combustion chamber volumes are:
P8R = 47cc
P75 = 45cc
The bigger combustion chamber volume will lead to a lower compression ratio, it's science, lol.

You can play around with different scenario's and plan your build with this:

http://www.zealautowerks.com/

On an otherwise completely stock B20Z with stock headgasket, the P75 head will yield 9.66:1, and the P8R head will yeild 9.37:1 compression ratios.

I completely understand, but the p8r uses a stock honda p8r 2 layer headgasket(there for bump in compression). If i were to use a 3 layer then i would lose compression(but honda doesnt make p8r 3 layer headgaskets.) I could use a p75 headgasket i guess. Thanks for the link Bill Nye the science guy.

9.51:1 with a P8R head and 2 layer headgasket is still lower than 9.66:1 that you'd get with a P75 and a 3 layer headgasket. Not much lower, but enough that it still goes down. The link rocks!

No. You can not use any VTEC parts in the nonVtec heads. Valve stem diameters are incorrect.