I'm about to install some forged CP pistons. How do I know which direction to install them since they dont have arrows? They are 9.8:1 compression and im installing them in an LS block. Looking at the LS pistons it looks like the larger grooves in the pistons are the Intake side and the smaller is the exhaust. Is this correct?

 

Correct, the larger valve reliefs are on the intake side. I just installed a set of SRP 10.5:1. What part of Tampa are you from? I live up in New Tampa.

 

as you mentioned the OEM pistons normally have an arrow on top of them pointing to the front of the motor, which is the timing side. forged pistons do not have this so you'll have to go by the valve reliefs. larger ones on intake side and smaller ones (normally with more of a gap between them on the inner sides) on the exhaust side.

just like said above.

BTW is a professional builder doing this?

make sure the piston to wall clearance is correct and that the cylinder walls are ready to accept the new piston rings. they should be bored straight and to spec, and then honed for the new rings. also the ring gap needs to be set according to the application, as well as the gap direction too. since it's 9.8:1 i'm assuming turbo. if so it's a good idea to "debur" the pistons for less hot spots.

hope the buildup goes well.