What is the difference between the left and right piston sets. In the parts manual the left and right pistons have different part numbers. I was wondering if I can swap pistons from side to side for a better fit.

 

I have never heard of different part numbers for left or right Pistons before. Have I missed something? What exactly are you using for a source for this information? Manuals are not always written correctly or accurately. How they are pressed on the Connecting Rod makes a difference left to right so that your "Squirt hole" is oriented to cool the bottom of the Piston and lube the Cylinders correctly and still have your "reference arrow" pointed forward for correct future re-assembly reference.


Wait, maybe...Are these raised top high compression pistons? This would be the only time I have seen different part numbers.

 

Bugout is correct. As long as the arrow, or notch, on the piston faces forward it doesn't matter which side they are on. But, I wouldn't recommend swapping sides with pistons/rings that have already "mated" to a particular cylinder.

If you're having runnability issues consider fixing the root cause instead. Otherwise, I'd say it's a crap shoot that you'll get "better fitment".

 

I guess my earlier reply didn't go through. The piston part numbers came from an OEM parts catalog. It lists three piston sized (b, C, D) and has separate part numbers for 1-3-5-7 and 2-4-6-8. The one issue I noticed is the oil weep hole where the rod cap bolts on. On both sides the weep hole faces in. Some where on the Internet I saw a comment about swapping by turning the swapped piston backwards so the weep hole is on the inside. I don't know if there's a difference as far as the wrist pin, such as an offset.

 

To the best of my knowledge, there is no offset to the wrist-pin. The weep hole must face in to lube the cylinder walls the way Chrysler engineered it on the 318 c.i.

The b, C, D are probably just stock and oversize piston part #'s. Why they have different part numbers for each piston, IDK. As Bugout originally stated, the arrow, or notch, has to face toward the front of the motor.

I believe the reason they're numbered 1-3-5-7 & 2,4,6,8 is as Bugout also stated. Should you tear it apart and rebuild using them, you want to put them back in the hole they came out of. It's a reminder. I personally wouldn't put piston #5 in the #2 cylinder, if piston #5 has already been in cylinder #5, for example.

If you don't mind me asking, what are you trying to accomplish by swapping them?