During that era I stuck with Super Tigers and never dabbled in the idea up upsizing a Fox from 35 to 36.
Assuming that the bore and stroke of the base engine was .8" and .7", a .716" crank would bring the engine up to .36 cubic inches, a gain of 2.3% swept volume, which would be significant in a close speed contest.
But it would also reduce head clearance by .008". If the engine was under-compressed to begin with, this would help. If the engine was correct to begin with, this would blow plugs and maybe the whole engine. In that era I didn't know of anybody who was actually measuring head clearance. But I did hear of a few who were stampeeding buy stroker cranks.
Is there anybody out there who actually bought a Fox stroker crank and got positive results?