Ideal spring rate?

[ootdega]

I changed the front shocks, and they work great, no complaints. However, the thing still swings like a half-conscious hippo around corners. So, it also needs new springs.

I read the sticky thread about suspensions, and done as much research on the subject as I can tolerate, but the spring rate formulas and equations make my eyes glaze over and go right over my head because I don't have the knowledge to put the information into context. The thread says to use 925/175 to lower it about an inch, but it doesn't really mention how that'd impact ride quality and such.

So I decided to just come here and ask about it. All I really want to know is what spring rate would give me decent cornering results without making the car go THUD.

[slack]

If it's just in cornering, how are you sway bar bushings? Usually when they're toast the car will lean big time in turns.

[turbo2256b]

If its never had new springs their probably weak. Coil springs go bad quicker than leaf springs if shocks were not changed often enough.

Ride has to do with a lot of things. Narrow side walls are one of he worst for ride like 285 30 x 18s on the front. 255 60s or 70s will ride nice with like 1000 lbs springs. Proper shocks, stiffer the springs stiffer the shocks need to be to control the spring.

[ootdega]

If it's just in cornering, how are you sway bar bushings? Usually when they're toast the car will lean big time in turns.

Sway bar bushings? I have no sway bars, you silly goose.

On that note though, the rest of the suspension bushings are, surprisingly, in great shape.

If its never had new springs their probably weak. Coil springs go bad quicker than leaf springs if shocks were not changed often enough.

Ride has to do with a lot of things. Narrow side walls are one of he worst for ride like 285 30 x 18s on the front. 255 60s or 70s will ride nice with like 1000 lbs springs. Proper shocks, stiffer the springs stiffer the shocks need to be to control the spring.

I've got brand new all-season 255/70's and brand new shocks, but before this the shocks were completely dead. Driver's side didn't move at all, and the passenger's would compress by hand with zero effort but needed Herculean strength to pull it back out. So combine that with what you said and the springs are definitely shot.

So, 1000s for the front. Sounds good. What about the rear? 200s?

[87gtVIC]

You need sway bars to remove sway.

[pantera77]

If you have no front swaybar you have bigger issues then weak springs...

[gadget73]

No amount of spring that isn't so stiff your teeth will rattle out will control body roll without the bars installed. Front is stock, they all had one. Adding a rear one is a highly suggested upgrade.

[turbo2256b]

Check the sway bar bushings first thinking the largest front bar is the Addico bar cant remember if the PI bar is the same or not. Another help is to install poly bushings in the sway bar frame mounts as well as the A arm ends. Check your bar diameter.

Stiffer springs will control roll more than any factory style sway bar for a Panther unless you want to make up some 3 piece NASCAR style sway bars which are on my dream list.

[87gtVIC]

addco bar is significantly larger.

[pantera77]

Addco is way bigger than even the 98-02 PI, but if he doesn't even have a rear sway bar, the last thing he should do is add a huge one up front.

[ootdega]

Sorry boys, sway bar's not gonna happen. Call me whatever names you want, not gonna do it.

I've been putting my efforts into producing results without them. Shocks, differential, tires, and now that I've done all of that, springs. I'll look into a tower bar too if I can figure out a concievable way to install one. When I do the brakes I'll also be adding a wider and stronger axle that has a Torsen differential available, and I'll see about adding a smidge of negative camber to the front.

But I'm not putting in sway bars.




So, what springs would be ideal for the rear? I'm guessing 200s. I've read that you should put slightly stiffer springs in the rear, but I can adjust the stiffness of the rear air shocks at will.

[gadget73]

Have fun with that. There are reasons that everything comes with a bar from the factory, and mostly has for the last half century.

There is no strut tower, so you can't install one. Those things keep the body from flexing. They do nothing to help with body roll.


Why no sway bar?

[ootdega]

Have fun with that. There are reasons that everything comes with a bar from the factory, and mostly has for the last half century.

There is no strut tower, so you can't install one. Those things keep the body from flexing. They do nothing to help with body roll.


Why no sway bar?

Yes, and it's the same reason that vehicles are now required by law to be able to support the entire weight of the vehicle on the roof, giving you blind spots the size of the moon in the process.

I know there isn't a strut tower, I replaced the shocks myself. Even connecting the two would be a feat in itself with literally everything in the engine bay between them. But every little bit helps.



No sway bar because I know how sway bars affect traction on uneven surfaces and off road. I have done my research.

And, having lived here all 24 years of my life, I can count the number of well-paved roads on my fingers. Out of every vehicle I've ever sat in, my car is by far the most comfortable and easiest to control, and that is in no small part because it has no sway bars. Absorbs bumps independently, keeps all four wheels on the ground, more ground clearance, and if one side gets damaged it isn't going to take the other side with it. Whoever owned it before me must have removed it for these reasons, if it ever had one to begin with.



Could you please answer my question?

[pantera77]

Sorry boys, sway bar's not gonna happen.
But I'm not putting in sway bars.

I don't know how to put this politely so I'll just say this is in the top 5 stupidest things I've seen on GMN, and I've read all of Matt's post.

[ootdega]

I don't know how to put this politely so I'll just say this is in the top 5 stupidest things I've seen on GMN, and I've read all of Matt's post.