my boy said the one with the 3 is high compression then the one ending in 5 this is stamped on the head also. idk the diff been researching it 4 like 3days and nothing some1 plz help i did find out there are 2 variants in the b20b one wit 9.2:1 compression and one with 8.8:1 but idk how to tell which one brings which and its not to b confused with the b20z with 9.6:1. i just want to kno if i have the 8.8 or the 9.2 idk how to tell. i kno i dont have the 9.6 though 4 a fact plz help me out

 

why worry about compression when you can put different pistons?

http://theoldone.com/components/pistons/

There ya go now you can run 11.#:1 or 12.#:1 compression on pump gas.

 

im worrying about it cuz i jus want to kno what is the actual difference that makes it have higher compression if pistons are the same

 

b20z is the newer one b20b is the older, 75-3 would be the older, 75-5 would be the newer, theoretically

 

There is no diff betwen the 2 head casting
The only diff that youll find is going to be, cams and exhaust springs if its B18b or B18a or B20b or B20Z all have diff exhaust springs... B20 and B18 intake cams are not exact the same.
Have the head shaved by .020 and youll raise the CR by .4

Have fun...
https://honda-tech.com/forums/all-motor-naturally-aspirated-44/b20-non-vtec-faq-guide-including-p8r-head-information-1467903/

http://en.wikipedia.org/wiki/Honda_B_engine#B20B.2FB20Z