Anybody run 1.19 torsion bars?

[JeffYoung]

Only a 340 lb spring rate per Firm Feel. That's not terrible, especially for a big block car.

Probably going to do it, plan on doing some auto-x cross in my car (72 U Code 4 speed Rallye Charger) and a few light track days once I get the brakes sorted.

[375instroke]

Stiffer isn't always better.  Even NASCAR guys talk about wanting to run softer springs, but the rules limit how soft they can get.

[JeffYoung]

This ain't NASCAR.....

Seriously, I do a fair amount of road racing and I can tell you that until you are overwhelming the shocks, or getting to a point where the springs are causing chassis flex, stiffer is almost always better from a road course handling perspective.

You want "soft" and squat particularly for drag racing. For road racing, it's all about maintaining the contact patch on the ground, and springs are the best way to do that -- stiff ones. Or in this case, torsion bars.

[375instroke]

Well, you don't want squat for drag racing either.  Real drag cars lift in the rear when they launch.  I guess it depends how much time you spend in the turn, and how much time you spend transitioning in and out of the turn.  Here are some SCCA race cars.  I didn't remember them using really stiff torsions, but I just checked, and some do.

Lame Horse Racing '66 Dart and '66 Formula S Barracuda
Team Starfish '66 Formula S Barracuda
'67 Barracuda
Make sure to read this: Handling line

[JeffYoung]

Nice links, thanks.

I may talk to the Firm Feel guys. They road raced an Aspen and a old E-Body I think. We'll see.

[FJMG]

  My cousin does that roadracing, when I rode in his 68 camaro I could not believe the ride! I expected much stiffer ride but it was way better than my mid-90's daily driver! I asked him about the springs and he told me his chassis guy keeps the springs on the soft side but the anti-roll bars on the HUGE side(makes my 97 2500 bars look like spaghetti). Claimed the cornering was all tires and anti-roll bar or something like that and that the springs carry vertical load not hriz. so unless the turns are banked (like nascar hence more vert load on springs) or vehicle was heavy (think Truck) no need for huge springs. However if you are not running large anti-roll bars then the car will roll more and definitely transmit more load on the outboard spring thus requiring more spring rate on that side.

[Mike DC]

   
Another vote for the "soft springs + HUGE sway bars" formula.

You might end up wanting the torsion bars & leaf springs stiffer than stock.  But in the big picture, the best way to clobber the body roll is with the sway bars.   


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The issue really governing the corner spring rates is the overall speed range (and the roughness of the road surface, if applicable). 


At 140 mph, you'll want some pretty stiff-ass springs under all four corners no matter what.  Even if you're land-speed racing in a straight line, you'll need to raise the spring rates as the speed goes up just to keep it off the bumpstops. 

On the other hand, at 40 mph on a rutted dirt road you'll want the springs as soft as you can get.  Even if the body is rolling heavily.

[JeffYoung]

Most road courses here are smooth, with speed ranges in the 60 to 140 mph range.

The big bars/soft springs is the old Colin Chapman/Lotus approach to street cars.  I think it a good performance street car approach.

In road racing, we always go as stiff as we can spring wise, until the shocks can't handle the dampening. The 1.18 bars are only about 350 lbs wheel rate per the Firm Feel web page which honestly is not much, and their Konis should handle that rate.

Then, we tune with bars.  In other words, think of the springs as the "course adjustment" to balance (oversteer/understeer) front to back, with you wanting as much spring rate as the car/surface can handle.  Then, you fine tune with bars.

Probably going 1.18 bars up front, Konis, and the Firm Feel road race leafs in the back, and see what we have.

Thanks guys! 

[RallyeMike]

I'm running 1.12's and they are plenty stiff for bumpy roads at very high speed.

1.0's, 140mph, and transition at a bridge = lesson learned.

[69bronzeT5]

1.0's, 140mph, and transition at a bridge = lesson learned.

I'd say

[Hemidog]

I'm running 1.12's and they are plenty stiff for bumpy roads at very high speed.

1.0's, 140mph, and transition at a bridge = lesson learned.

Ouch, what were you leaking? tranny fluid?

[RallyeMike]

8 Qts of Mobil 1.

[Finn]

What would you guys recommend for daily yet performance minded use? (68 charger, 440/727, 4 link rear, Air-ride suspension)
Also, this is totally a noob question but is there a left and right/front and back to these things?