Rear suspension options

[lisiecki1]

I have a '73 and I'm researching rear suspension options, in case I want to do some major fab while the car is apart.

Contemplating the pros/cons of doing a panhard setup vs. updating the factory leaf setup.

Purpose of the car is a nice driver, capable of spirited performance but no intention to have it in any race events.  Solely for driving/cruising pleasure.

Due to this, I'm thinking an update of the factory leafs and a mini-tub and leaf spring relocation with the addition of poly bushings throughout will be plenty.

I am interested in hearing others thoughts and reviews of what you have gone with and how you are enjoying it.

Links to write-ups/articles/manufacturers and parts are greatly appreciated.

[Mike DC]

 
How much of a factor is drag racing/launching from a stop?
 

[lisiecki1]

Itll definitely happen.

I'm also currently researching different styles of 4 link.

So many options.  I'm leaning heavily towards a triangulated 4 link.

[Mike DC]

                        
When it comes to all-around handling, IMO the biggest issue on the rear end is the steel leafs.  Lots of unsprung weight + very stiff spring rate (to help control that unsprung weight).  A big part of the gains from the 3/4-link setups is ditching the leaf weight in favor of coilovers.  


The 3-link (plus a panhard or watts) is arguably the best choice for handling geometry.  The 4-link setups can work pretty well too but their ideal range of suspension travel (up/down) ends up being narrower.  4-links are more prone to bumpsteer than 3-links and the roll center isn't as easy to adjust by itself.  That has a lot to do with why racers like 3-links: adjustability.  OEMs build a lot of 4-links because they can design it once and most car owners will never try to play with it.


Going to fiberglass leafs can help lose some weight if you don't wanna go to a 3/4 link deal.  

A lateral control method (panhard or Watts) is mandatory on a 3-link.  It will make a noticeable difference even on a leaf-sprung rear end.  But a set of leafs can do the job tolerably well by themselves if the bushings are fresh.  

Leafs + panhard/watts = some amount of binding.  Keep some rubber bushings in that setup.  

[Nacho-RT74]

if keeping stock, but reinforced, springs sliders instead the stock shackles could be an option

[b5blue]

I added a cheap rear sway bar to my 70's M.P.-H.D. rear springs (ADDCO K1-919-0U) and it really helped the car stay flat in the corners.

[Nacho-RT74]

Oh... yes... and rear sway bar. Didn't think on that because was a stock option offered since 72 ( standard on Rallyes )