For LS vtec, do you need custom pistons like b20 vtec?

 

you can if you want, but no

 

I'm using ITR's but you can use stock ls pistons if you like

 

lsvtec you dont need custom piston. cause a b18a/b block and b16/b18c/b18c5 all have the same bore size. Which mean same piston size. If I were you i'll either go with JDM ITR piston in a lsblock with b16head give you like a 11.4 cr. CTR piston in a ls w/b16 give you a 12.4.
good luck!