Does anyone know what the difference between a floating wrist pin and a press fit pin are? What keeps them from moving back and forth (side to side) in the piston?

 

Floating pin pistons are fitted with retaining rings in the pistons.
http://www.tpub.com/content/engine/1.../14037_104.htm

 

I see, thanks. So what is press-fit? Is it like the fixed pin?

 

Floating wrist pins also require bushed rods. The bushings in my stroker rods are bronze. The floating pins actually rotate, wearing and making an oval out of the small end of the rod. The bushings are an interference fit, and can be pressed out and replaced when worn. My pistons also use larger .927 diameter pins, as opposed to the stock .912. They're a little heavier, made from tool steel, and have a thicker wall. Floating pins allow the piston to move more freely, reducing friction losses, but they can also contribute to piston "slap" against the cylinder walls. To combat this, I went with teflon coated, full-skirt forged pistons. These features allow you to run tighter piston-to bore clearances, which also enhances ring seal and stability. Press fit pin side-to-side movement is limited by the pin bosses that are cast into the bottom of the piston.

Pete

 

I was just looking on summit for some pistons and realized I didnt know the difference between press fit, and floating. Although quite self descriptive, there were parts still unclear. Thanks guys, do you happen to know what type come from factory in 351c's, Windsors, and 302s?

 

The guys in the engine forums would know.

 

351C, 302 and 351W all use press fit pins from the factory as far as I know.