when im checking out pistons i see these numbers in the description:

C/R: 58cc - 11.2:1;
64cc - 10.4:1;
70cc - 9.7:1;
76cc - 9.1:1.
1.250'' C/H,
6.0'' Rod,
3.480'' Stroke


does this mean if i use 64cc heads, i get 10.4:1 compression?

also what is that 1.250" C/H?

and 6" rod is self explanatory, and im sure the 3.480" stroke isnt a big a deal? these will be going in a stock 350 thats bored 30 over

and these pistons are for 4.030" bores. fyi

 

you're correct on the compression ratio
CH is compression height
6" is rod length which you don't have with a 350 you have a 5.7 rod
3.48 is stock stroke on a 350 and 305.
you need 6" rods to use the pistons. the wrist pin would be in a differant location from a piston made for a 5.7 rod.

 

So that means I need pistons with 5.7" rods?

and then get 5.7" rods? thanks!

 

as i check out diffferent pistons i see (both are for 350's it says)

some are 6" rods and others require 5.7" rods

and some say 3.480 stroke and others are 3.750" stroke


my block is gonna be bored 30 over (4.030") so which stroke should I go with? and because this is a 350 from a camaro, I assume I have to use 5.7" rods? thanks again!

 

you can use either rod you want 5.7 or 6 just match the pistons to the rod. same with cranks 3.48 is stock 350 stroke. if you want a 350 use a 3.48 crank.

 

Yeah, just match up to the piston description what you are going to use rod and crank wise. Like he said, 3.48 stroke is stock, if you what to make you engine a stroker, 383, then that has the 3.75 crank. Same with rods, 5.7 is stock length. Some builders use the longer rods, 6.0".

FWIW, if you use a 5.7 piston with a 6.0 rod, your pistons will stick up over the deck and that is bad...

 

You have to qualify the listed compression ratio ratings.
The ones for those pistons are for a "0deck height block".

Would require you to remove about .025" from the block decks to achieve this.

Those pistons in a stock deck block would make a 9.77:1 cpmpression ratio with 64cc heads. The pistons would be about .025" down in the bore at TDC. ( approx)