I need help picking an appropriate spring rate for a new set of leaf springs for my '73 Dart (100% street driver, no racing, no towing).

Unless I'm mistaken, the car has standard basic springs as factory equipment, not the optional HD stack. According to Eaton Spring (see PDF catalogue at bottom of page), the standard springs (both 4-leaf slant-6 and 5-leaf V8) have a rate of 85 lb/in, while the heavy-duty springs (6-leaf) have a rate of 110 lb/in. Looking at earlier-year listings in the same application catalogue, they show the station wagons got 110 lb/in 5 or 6 leaf as standard, and 130 lb/in 6 or 7 leaf as heavy-duty. The Hotchkis spring setup is advertised at 130 lb/in.

Some additional "carry crap in the trunk without sagging" capacity would be nice, but I still need the car to ride smoothly on streets that aren't in the best condition, and I don't want to make the car tail-happy on slippery roads.

Advice will be much appreciated -- thanks.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Get the heavy duties....they are still too soft.

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Yeah....Im the one who destroyed this rare, vintage automobile.....

yup.

Thanks. Which heavy duties? 110 or 130?

I can get a 110 lb/in (4- or 5-leaf) or 130 lb/in (6- or 7-leaf) stack from Eaton for $479 + shipping

I can get a 130 lb/in (4½-leaf) "geometry corrected" stack from Hotchkis for $350

Any reason to prefer one over the t'other?

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

What's the front spring rate?

Check this out:

http://www.optimumg.com/OptimumGWebSite ... _Tip_1.pdf


You don't want the spring rates F/R to work together to give you a crappy ride......

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

*blink blink* :shrug: It's a factory 225-A/C car so it's got 892-893 bars ex-factory, same as 318 cars got. I don't know what the spring rate of those is.


Interesting document, thanks for the pointer.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

.890 is 120

http://www.slantsix.org/forum/viewtopic.php?t=35999

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes