Got an intake gasket for a 3RZ here. There's a convex and concave side. Do you know if one side points to the head?

Who supplied the gasket? Ask them.

Toyota OEM. Guess I could pose the question to the dealership. I'd trust an answer most from a forum member here.

I have a 6 cyl, but the intake manifold gaskets for the 3.4L are similarly bent like that. I made sure that the gasket was symmetrical facing either way (it was) and then I put the flatter outside section facing the bottom. My logic was gm exhaust manifold gaskets have similar bends, but the gm ones are labeled for the outside flat section against the cylinder head and the bent portion goes towards the exhaust manifold. I'm not sure it would make much of a difference for intake gaskets, but I haven't had a problem with it since they were replaced a couple years ago.

EDIT: By flatter side I mean the outside edge portion mating with the head and the inside raised portion toward the intake manifold. I hope that makes sense.

If both surfaces are flat then I'd put money down on saying it doesn't matter and you can toss it in however you please