I was wondering if anyone knew the compression height of a B20Z stock piston?? I have seen that the B20B pistons are 1.165" but so far I have been told they are not the same. I have a B20Z piston here and from what I have measured I get a 1.157" I have also asked another guy and he said that he got the same measure. But I was wondering if anyone had a definitive number? Because I know I could have measured wrong!! LOL Thanks for any info.

 

I am looking at my CP catalog and it's 1.181 for B20B's.


Hope that helps.

 

Hey thanks for the reply. I think that most of the aftermarket piston manufactures are making their pistons for the B20 motors with a compression height of 1.181".

I finally got my hands on some good equipment for measurement and I came up with a compression height of 1.157 for the B20Z stock piston yet again. But now that I add half my stroke ( 1.752") + my rod length ( 5.394" ) + my compression height ( 1.157" ) and my piston to deck clearance ( 0.038" ) I get 8.341" which should equal my deck height of a B20/B18 block, assuming crank center to top of deck equals deck height.

The best reference I can find for B20/B18 deck height's lists it at 8.347" I am wondering where my other .007" is? Giving small measure losses for clearance at the wrist pin, rod journal and crank journal still should not add up to .007" I am wondering now if my reference for B20/B18 deck height is valid? I have triple checked my measurements on all parts so I am confident now that it all add's up to 8.341"

I would be interested in any comments, that is to say if the topic is not to boring!! I am new to this end of things and maybe I am over looking something.

Thanks again

 

I haven't measured the deck on B20's but it's probably the same as a B18. The lower CH on B20 pistons give them less compression. So I would say your okay running 1.181 CH.