rear spring rate theory for gassers?

Should a gasser rear leaf be on the stiff side like current racecar theory, or does the "gasser" set up require a softer rear springs?

The leafs in the car may not be original Falcon (just recently got the stock leaf length specs and i'll compare the installed length soon) but they are SOOOOOOOFT. Atrociously soft.

When we set the front leaves and bounce tested the front action- the REAR of the car started to oscillate like flipping a bullwhip

The shackles are loooooong and installed at about a 45* rear angle- and some suspension design specs i've seen tell me that's good IF when the car launches, the rear of spring goes down, pulling the shackle forward, lifting the back of the car and loading the tires even more-

Might end up clamping the front halves for stiffness? any thoughts on preferred spring action when it's a gasser not a modern chassis?


rick

 

No gasser guys tonight?

-rick

 

All you need is enough spring in the front to keep that Solid axle off the oilpan, when it comes down, and enough rear spring to make those fat skins bite into the track hard enough to pull the wheels up in front in the first place.
After that, you just wind her out until she quite pullin , then garb another gear. When you've gone thru them all, keep it floored till you cross the finish line. Main thing is to stay in your lane!
Come to a stop, open the door, pull out your storm-proof zippo and light up a camel to sooth your nerves...

 

A gassers rear springs should be fairly soft....for the rear to squat and bite. A 55 is a heavy car, so, unless you've put her on a big diet, your gonna wanna run a 2 or 3 leaf setup on each side.
When you pull all that weight onto your rearend, you don't want your suspension bottoming out unless you got snubbers set to keep things from bottoming out hard. I use traction bar snubbers off the Lakewood traction bars.
But you want to throw all that weight onto the rear suspension....just before it bottoms out....and have your tire pressure down for the slicks to bite....

 

LOL! I've reconfigured the sump for clearance, got the Zippo, but after 23years finally pitched the Camels (no cancer of the hump for me!)

It's actualy a 61 Falcon- the Mopar 8 3/4 rear has the factory pinion snubber still, but i'd replace that with the adjustable Mopar piece if i run it.

The Falcon itself has a pinion snubber on the underside of the driveshaft tunnel- so that's another option

3rd, I have a vintage set of traction bars (Ansen? maybe not?) that I like because they are old, have integral shock mounting points, and have that crazy rear snubber, but they aren't boxed and i think i might just lay that U-channel open with a BigBoy launch....

-this is the pic from the previous owner(you'll have to ignore his stash of of Barely Legal Bong-B-Fresh bottles,lol)




I'm considering all ideas-juggling rear leaves, adding leaves to the front half, clamping the fronts, unclamping the rears, replacing with a Mopar SuperStock pack (Short front half, long rear), and one old timer told me of good luck he had by flipping the shorter leaves end for end so that the longer portions were pointed towards the front to stiffen the front half even more and let the back half be loose.

the rear shackle spring end points to the back- so in theory: if the axle twists, it will pull down/in on the rear eye and the shackel will stand up vertically lifting the body/pushing down on the tires even more-

Sound legit? Any other ideas, or anyone actually recommend a rear spring rate with or w/o ladderbars? car should be about 2900lbs wet.

thanks
-rick