340 pistons in a 360?

don-vee said
So, I have heard of a few guys doing this in the old days, using 340 pistons in Now, I was just TOLD they were 340 pistons when I bought them at the swap, but how do I check and make sure? What are the differences? Maybe the guy sold me 360 stuff instead, it's happened to me before.

Check compression height (center of pin to top of piston):

68-71 340 1.840
72-73 340 1.740
71 360 1.584
72-86 360 1.591

Although a machinist ruler would be preferable, I think even a Stanley tape would be enough to detect the difference.