Many times on these forums I have recommended mounting a video camera underneath the car with good lighting, then making a pass. You can see real quick what's goin' on under there. You could even mount a pointer on the pinion retainer that would register on a flat plate or board under there and tell you exactly the angles that are in play.

Different types of rear suspension will require different set-ups in the first place. The pinion on a leaf spring car will climb the ring gear more aggressively than on a triangulated 4-link system, for instance.

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