i am getting a B20 block with in the next month and i am going to upgrade the pistons but i want to stay OEM and i am not sure if any pistons will fit it, if so will they need any modification. if they dont fit which pistons will. i am also going to upgrade the oil and water pump to ITR. will this setup be able to run a reliable VTEC. can i run a LS head on the B20 or should i just get the complete longblock because my LS head is getting built. thanks any info will help.

 

the bore on the b20's is 84mm... so you need an 84mm piston... none of the other b series pistons (itr, ctr, ls) or anything of that nature will work as they all go in 81mm blocks. you have the choice of the b20b or b20z oem pistons, aside from that i don't think there are any other oem pistons that will fit, except for maybe those old prelude motors...hmmm... not really sure though...

you should take a look at these sites also. http://www.crvtec.com http://www.b-20.net

also, you're not gonna be running vtec with an ls head....if you want vtec you need a vtec head.