View Single Post
Old 10-07-2020, 05:52 AM   #18
glennpm
Senior Member
 
glennpm's Avatar
 
Join Date: Sep 2014
Location: Wiscasset, Maine
Posts: 1,981
Default Re: Different Key ways??

Here is a picture of both of the 32 Pitman arms with the "B" or truck one on the top. There is a one tooth difference between the two.

The rotation of the B would push a fixed length drag link further to the front of the car and deceases the desired 90° between the steering arm and the drag link.

If you you have a B as mentioned above, you can either remove the indexing teeth at each 90° or file those indexes to make 8 new teeth. Either way would allow you to place the pitman wherever you need to maintain the 90°. All else being correct, one tooth CCW.


This morning I had a thought. How much angular movement does 1 tooth give you?
There are 36 teeth (the 90° apart "keys" count for 2 teeth each) so 360/36 gives you 10 degrees at the Pitman arm. For a stock 1932 with 13 to 1 worm/sector shaft ratio, 1 tooth would be 13 X 10° = 130° steering wheel rotation!


Glenn
Attached Images
File Type: jpg B Pitman arm on top of an A with Splines Aligned.jpg (33.3 KB, 353 views)

Last edited by glennpm; 10-08-2020 at 07:43 AM. Reason: Impact of a 1 tooth rotation
glennpm is offline   Reply With Quote