That's ok Chuck. This is not a race or an election but I've probably forgotten more than I can recall at any given moment. If we are keeping track, I said a 1/2 degree minimum for lubrication 15 years ago but have changed my mind since then and my experience with miata driveshafts is older still.
If the miata joints were greasable, then there would be no issue but it eventually breaks down and allows some minimal movement that increases the clearance. Even so, they last a long time. Back then, compact digital protractors were not common or affordable and the ppf makes it difficult to measure anyway.
Of course, if you are direct measuring lateral offset in order to do the math with straight edge and a manual (since a pendulum doesn't work) angle finder, then you could just rotate the rig around to find the greatest angle.
But yes, Chuck is correct about the actual, true operating angle being greater than the largest angle shown vertically or horizontally if both are greater than zero.
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Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS
viewtopic.php?f=5&t=13225&p=134742Simple Spring select
viewtopic.php?f=5&t=11815LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12