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Owen.
Just out of curiosity, did any of the Packard 8's u got into have pistons with no slots in skirt???? The only reason i ask is that i have seen non slotted pistons in engines that were supposed to be slotted.

I have never seen an OEM piston in a Packard in-line 8 without an expansion slot; I have seen some aftermarket pistons without them, one as I recall was a Sealed Power replacement piston for a 356.

As noted the straight eights do not have offset wristpins. However by my less than exact measurements, the cylinder bores are offset 1/16" relative to the crank. The chief purpose of this is to reduce side thrust on the piston during the power stroke. Simple, clever, effective. Packard.

Thank you Ross and other contributors for adding to my knowledge ( perception more likely) of what I believe was an "edge" which Packard used but did not promulgate (make widely known). It is interesting to note that all of the Post WW11 inline auto engines ( 245, 288, 327, 356, 359 ) had a crank journal diameter of 2.7465in. When you add the up to.003 main bearing clearance, it takes you up to 2.749. Which is very nearly 44 times one sixteenth of an inch. I would therefore estimate that the Desaxe is approximately 8 degrees. This common dimension for crankshafts would carry over to block machining for crank bearings and allow the Desaxe offset to be incorporated in all of the post war inline engines. I re-iterate that my readings on the theory for the Desaxe is that is makes an engine less likely to stall when idling slowly. I have always appreciated and been complimented on how Packard in-line engines idle so smoothly without any appreciable stumble. It is also interesting that many modern engine designers are apparently turning to desaxe design to enhance certain engine performance characteristics. Best Regards and if anyone has any objections or corrections to my observations, I would be quite pleased to be corrected. There are very knowledgable engineers out there, whereas I am merely an interested Packard nut. PT