I sent my motor to get sleeved at rs and i need to know what size pistons i should get. I will be running the vortech aftercooled system. The most psi i will run is 18. What would be a good size piston.

 

bump

 

What block are you working with, if it's a B series anything from 81-84.50mm should be absolutely fine. You probably could go with more but we never do. Just my $0.02 tho

 

it is a b16. you dont think that would make the walls to weak.

 

Not with a sleeved motor, Duc's B18C is at 84.50mm (actually just about all of the FI motors we ever build now are) and it holds 30lbs. without any problems what so ever. We're going to tune Will's 84.50mm FI B16A/Rex today so we'll see how it holds up, it should be making ~500whp at higher boost levels than you are looking at.

 

Here's a suggestion, depending on how much money you have:

Start off with 81.5mm or 82mm. If you are not satisfied with the torque, buy new pistons and bore/hone it to 83mm..so and so forth. If you do it this way, you will have saved yourself the time and money from sending back and forth to RS because you went to big and cracked a sleeve the first time and then spending the money for the pistons/bore/hone.