Skunk River Restorations

OUCH!

Torsional stiffness of A 7/8 bar is 1.85 % more than the stock 5/8 bar.
Torsional stiffness of a 1.0 diameter bar is is 3.16 % more than the 5/8 bar.
Torsional stiffness of a bar varies with the 4th power of the radius.

All those numbers hurt the remaining brain cell . . . . .
 
Looks Low

I would have expected the differences in torsional rigidity to be much higher than the few percentage points. Looks like a lot of effort to gain only 2%-3% increase in stiffness.

David
 
I punched in some very arbitrary numbers into my Torsion/Sway bar rate program and using those values.. I got 195 lbs./inch for a 7/8" bar... inputting a 1" bar pushed it up to 333 lbs./inch
 
I'm still holding off on reinforcing the clips on the street Tiger. I'm trying to learn if they're still needed with a better fitting bar.

bt

Aug 1983, 1" swaybar mount (un-reinforced) failed in middle of corner.

It can happen.
 
sawy bars

Torsional stiffness of A 7/8 bar is 185 % more than the stock 5/8 bar.
Torsional stiffness of a 1.0 diameter bar is is 316 % more than the 5/8 bar.
Torsional stiffness of a bar varies with the 4th power of the radius.

Sorry but decimal points got in the way . I stand corrected!
 
Sorry but decimal points got in the way . I stand corrected!

My theoretical 24" long bar with 12" arms shows a 5/8" bar @ 51 lb./inch vs a 1" which computes to 333 lbs./inch ! That's 6.52 times ... or 5.52 times ( 552% ) more !

I tried using a bar length of 20" and the ratio between the two different diameter bars was about the same...

I got the handy calculator program here...
http://www.circletrack.com/car_racing_calculators/torsion_bar_rate_calculator/photo_01.html

It runs in Microsoft Excel ...
 
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A Very Long Time Away

I punched in some very arbitrary numbers into my Torsion/Sway bar rate program and using those values.. I got 195 lbs./inch for a 7/8" bar... inputting a 1" bar pushed it up to 333 lbs./inch

The circle track grease monkeys who played with my Tiger's suspension back in the mid 60's put some emphasis on heavy rear sway bars (plural, yes) with unequal arms to take the working strain off the front. At the time, my interests did not include following the geometric reasons and there are no photos, but the concept seems to be a sound idea. . . . .
 
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