I have a couple questions. Could i run pump gas with 12:1 pisons(91 octane). I have a b16head 81mm b20 is 84mm should i get the combustion chamber *deshrouded(is that the right word?) to lower cr and resist detonation, and how much would that cost. Also with these pistons would i be able to switch over to ctr cams with out smashing the valves into the pistons

thanks in advance

 

good question,

also what pistions are you going to use?

 

jg 84.5 mm