Calculating a turning radius....

[lalessi1]

I have posted before questioning if (or how much) a rack and pinion set up increases turning radius. I found myself really bored on a rainy day so I decided to do a little geometry exercise and come with a simple way to calculate a turning radius. I made my measurements with a 6" plastic protractor, a couple of straight edges, a square, a pencil, and my phone calculator. The results were surprisingly accurate, (published turning diameter is 40.1 ft curb to curb). If anybody cares to measure full lock steering angles this formula will give you the turning radius.

P.S., I was REALLY bored!

[Zapato]

Next time that I find myself really really bored am going to go out and measure every car we own and plug in the numbers and compare to all the published results. Come to think about it who has time to be that bored. Anyway looks like it was a interesting exercise for you.

Zap-

[lalessi1]

I thought everybody does this kinda thing....Lol. It is pretty sad I know.

[RICH MUISE]

I wish I had your math skills, or at least the math skills I use to have,lol.  Actually...kinda odd the way we think of it..we call it a turning radius, but we're talking a 180, so it's really a turning diameter.

[lalessi1]

The little bit of looking I did online I found there are turning diameters for some cars published both curb to curb and wall to wall. I thought that interesting. All I found for mine was curb to curb. I am concerned about it because I have tight turning clearance to get into my carport. My driver has a 34.5' turning circle and the Ford feels like an aircraft carrier in comparison. I don't want to make it worse without understanding how much worse. I can use bolt stops on the pittman arms to simulate an RP steering radius. I definitely tend to overthink things though...sometimes a blessing other times not so much.

[Jeff Norwell]

Wow Lynn,you had me at the wheel diagram, After that,I need a tutor!
ha ha

[jseth83]

That's awesome, thanks for sharing!  Where did the .895 come from?

[lalessi1]

It is the cosine of of 26.5 degrees. I measured the angles of the outside wheel and the inside wheel at 26.5 and 36 degrees. The cosine of 26.5 is .895 the tangent of 36 is .726. These values came from my phone calculator.

[jseth83]

oh ok that makes sense.  Awesome, thanks for sharing!