Originally Posted by 65Xchevy II
Don't forget this piston will travel an additional 1/8 inch in the cylinder both directions leaving you with a deck clearance of .016 compared to a normal 350 of. 125. This will have a big impact when calculating you compression ratio. Make sure the piston has a compression height of 1.43, this raises your wrist pin on in the piston to reduce the cylinder sidewall pressure and keeps your piston below your deck.
I don't think you understand "stack". That is the sum of all the parts used in the build. The small block Chevy is ~9.025" block deck height. You have to use a "stack" of parts that will fit into that space......like this.....
350 uses 1.560" piston, 5.7" rod and 1.740" crank radius for a stack of 9.000".
383 uses 1.425" piston, 5.7" rod and 1.875" crank radius for a stack of 9.000".
What you are doing is using a shorter piston to make up for the increased stroke radius, so that you keep the "stack" within the confines of the block deck height.
Same with any small block....
327 uses 1.675" piston, 5.7" rod and 1.625" crank radius for a stack of 9.000"
283 uses 1.800" piston, 5.7" rod and 1.500" crank radius for a stack of 9.000"
Putting a "stack" together has little to do with reducing cylinder sidewall pressure. It simply entails fitting the proper "stack" of parts into the available space.
Here's an example of a D-Cup hypereutectic piston from Keith Black. See the large, flat pad on the piston crown in the left of the photo? That's what Big Ed is talking about when he says that you need a flat area to mate with the underside of the head to form the squish.