I BOUGHT A B20 THE OTHER DAY AND THEY SAID IT WAS A B20 HIGH COMPRESSION.THEY TOLD ME THAT HIGH COMPRESSION SERIAL # STARTS WITH A 5 AND THE LOW COMPRESSION STARTS WITH A # 3?IS THIS TRUE?HOW CAN I TELL IF IT'S HIGH OR LOW????

 

if its a b20b than it has 8.8:1 cr
its its a b20z than it has 9.6:1 cr not high compression but higher...

 

yea i know that...but thats only for U.S.D.M......BUT IN JAPAN THERE IS NO SUCH THING AS A B20Z THEY ARE ALL B20B.. ON THE HEAD IT IS STAMPED 9/7 MEANING 1997..AND IT ALSO IS STAMPED P38..<--THATS HIGH COMP RIGHT? LET ME KNOW PEOPLE..GRACIAS

 

if it has a knock sensor its the high compression. if not its the low compression