I can get some ctr pistons in 81.50 or 81.75mm, to put in a b16a2 engine. I need to know if the engine will support one of this bore...let me know your opinions to complete my all motor crx project.

 

They make 81.75 OEM pistons?

I thought they topped out at 81.5.

At any-rate, just go 81.5mm

 

if those 81.75 are ctr's, they're most likely the .25 over sort. this is fine and you'll have plenty of room in your block. you will need to have your block machined and bored for the larger pistons. bigger is always better too in my opinion. im not sure if you have to mod your wrist pins to accept the ctr slugs, but even if you do, it wont be expensive and definitely worth it! good luck