mahle vw piston orientation

[maxyray]

Hi All,

I'm just about to install a set of mahle forged 90.5 pistons.

My question is this...

Is there a top and a bottom to a Mahle piston? I've been told that the piston pin sits off center.
I know that the arrow on the piston points the the flywheel.

[Marc]

Yes, the wristpin is slightly offset to one side - installing them with the arrow pointing towards the flywheel orients them correctly in relation to the direction of rotation to reduce piston "slap" and noise.
There's no "top" or "bottom" to concern yourself with unless the piston tops have been notched for valve clearance.

[maxyray]

Ok got it.