{Chrysler 300} Torsion Bar Diameters

Hi All,

I know I have asked this before. In the next few weeks, I will rebuild the front end of my 1964 300K single 4BBL.

What I need from the group is a very careful measurement of the front torsion bars for a 1962 300H, 1963 300J or 1964 300K RAM. When I say careful, I mean it as factory torsion bars are produced with diameter increments of only 0.020. A small increase in size makes a big increase in spring rate.

Even when cleaning a bar to take a measurement, if one uses sandpaper or the like to get through the paint, that can remove 0.020.

I am hoping two or three of you can take some lacquer thinner and clean a spot on your bars, assuming you have access, and take calibrated caliper and measure your bar. I think it should be someplace around one inch.

Some bars that I have out of a car are:

709 Bar = 0.983

708 Bar = 0.982

I have been told that a 1962 300H also has the 606 and 606 bars which should be the same as 300J or 300K RAM. That bar is reported to be 1.01 inch and has a rate of 130 pounds. My problem is that one source says that the 1962 rate is 130 while the and the 1963 is 125 all the while the part numbers are the same (606 and 607)

Given that a .002 change in diameter makes a big change in spring rate, I am trying to do exactly what the factory did and not guess or play around. To date, I have not been able to find a set of 606 and 607 torsion bars. The folks at Firm Feel have a new set they made, at 40 inches long which is 1.060 which I fear may be too much.

Decades ago, I ran across a 300 parts car that I purchased that had the RAM-Trailer Towing package on it and I took it all off and used in that 300K hardtop. It was a big improvement in handling without being too harsh. That is what I want to achieve now.

This is why I am asking for help. A good list of the bars and the exact diameters would not be a bad thing to have.

Thanks all, James