Im confused about my Rods

[MeMadMax]

I think my machinst screwed up. Im rebuilding a 3.1 out of a 96' Grand AM and just got my lower end back from the machine shop. Everything looks great except for the pistons/rods. I think the even bank pistons are on backwards. I know about the notch on the pistons facing toward the front of the motor but what about the rods??? On the big end of the rod on the Odd bank there is a little "bump" that faces toward the front of the motor. The bump is at the top of the bearing where the bearing ends and the rod begins. But on the other bank the Bump faces the rear of the motor. Does anyone know if this supposed to face the front, rear??? I would assume the front but I just want to make sure. Just dropped 2k into my bottom end and dont want to make any stupid mistakes.
Thanks

By the way my number stamps face outward on these things(all of them do) but I had managed to confuse myself since this build is takeing so long.

[Guest]

I don't think it really matters. Since the rod is pretty centered on the piston and each rod has it's own journal. I've also tried to see if there would be any block interferance by turning them around and could find any. IIRC there were a couple rods that were turned like yours are and my engine ran just fine.

[tractorman]

The GM service manual for my '94 Corsica makes no mention of rod orientation. It just shows which way to point the pistons.

I've rebuilt many dozens of engines (mostly diesels), and I've seen the locks turned to either side (even on opposite sides of the rod bore in a few cases), so I know that this isn't an issue. I've also seen (in a few V8 automotive engines) the rods turned differently in the same engine... with no apparent effects.

Never rebuilt a 60 degree V6, so I'm not speaking from direct experience here... but I would look real close and make sure that the rods are machined symmetrically (not offset in any way). If they are, then I'd slap it together, make sure there are no clearance issues, and not lose any sleep over it.

[boostedrs]

when i did mine i put all the tangs in the caps to the outside(i.e closest to the oil pan rails) thats how my motor was from the factory as well.

i really dont think it matters,the reason the pistons have to be faced the rightway is cause the pins in the pistons are not dead center of the piston,they are offset to one side

[MeMadMax]

Hey guys thanks for the reply!

The official word from the dealership is: It doesnt matter. As long as the cap to the rod matchs (where the balance grind is) and of course the piston notch points to the front of the motor. In this case all of my bearing tangs or on one side of the rod. Kindaof no brainer but why take chances when a huge amount of money and hard work is at stake. Motor is turning out really well hopefully post some pictures here soon.