off season pondering pinion angle

[Dave Gantz]

Don, you have the right idea, imo. I've always heard all of the different angles for different suspensions. I've always wondered how anyone really knew what it looked like under there to recommend a given angle. I wouldn't know how to put whatever camera under a car to see it working (not to mention I'm hardly ever at a track anymore), but it would be interesting to test a large sample of cars and see if these recommended angles are working.

[Jeff Lee]

What is it that measures shock travel and records it on the data logger? Whatever that thingamajig is called, you need to fabricate one for the nose of the differential and actually measure the movement from the base angle. You could build a mechanical apparatus not using a data logger.
I know a guy that was video'ing the movement with a strobe light on his BBC SS car back in the '80's. I don't remember if it was a 4-link or ladder bar car. But as I recall, it was difficult or impossible to keep the pinion angle below zero with shocks and chassis tuning that would enable the car to launch correctly. This was a National record holding car.

[Tom Goldman]

Performance Trends' 4 Link software has a very good pinion angle program. altho limited to 4 link and ladder suspensions.
it allows you to input all the relevant driveline angles and it will put it into animated motion and allow anaylisis of the changes thru the suspension travel.
Not a 100% susbstitute for on track experiments, but it does give some insite into the possible pinion angle changes a given setup will yeild.