71 b body set ups give me some pointers.

What I have.

71 sat 440 with air grabber has all original 318 torsion bars/springs, never had any sway bars has 4 wheel drums.

I put a pst polygraphite kit in it after it was taken off the road in 94with 0 miles on it so new ball joints /control arm bushings tie rods and sleeves.

Right now I'm set towards the doctor diff brembo style front and cobra style rear brakes.

Will these eliminate any type of sway bar choices?

Sway bars, my lower control arms have no mounting brackets, does anyone sell the brackets so i can weld them on or am I just better off finding a set with them and rebuilding them?

Or do they have aftermarket set ups that bolt on differently?

Torsion bars and springs, as much as I love cars that handle I also love the nostalgic muscle car look.

Not really keen on the idea that hotchkis springs lower the back an inch.

Wheel rates how hard is it going to be to match a good set between the front torsion bars and rear springs?

Steering, not real fond of the factory box and would like something a bit more responsive.

What are your suggestions.

I'm not too familiar with B Bodies... But you say you like the nostalgic muscle car look. What size wheels do you plan on running on your Satellite? I know for a fact I could not fit 17" wheels with the Brembo-style brakes on my Dart.

Torsion bars shouldn't be an issue for looks as you can adjust the ride height to your choosing. I'm sure there are plenty of other options for leaf springs to give you better handling and a similar ride height.

Hotchkis isn't your only option for sway bars. I'd also look into Hellwig or Firmfeel. Some kits may offer the mounting brackets and I think Hotchkis might sell them.

For steering, your better upgrade is the Borgeson power steering box; however it's pretty expensive and some people have had difficulties with instillation.

I'd also invest in a good pair of shocks. Minimum, Bilstein's from PST (I believe they sell them) or get Hotchkis's non-adjustable ones.

I was going to use 17 inch mustang rims I had sitting around.

I was gona go with the brembo style because I have the cobra brakes (on a mustang) and while they are nice I kinda wanted an upgrade.

Do they have wheel rates listed for springs and if so how should a front wheel rate compare to a back one?

I'm running the complete Firm Feel suspension on my 71RR airgrabber car. I considered a brake upgrade along with 17" wheels and tires. Dick at Firm Feel told me it wouldn't be a problem.

You are asking a lot of very basic questions so you might want to start off with the book I wrote on B-body performance upgrades. You can get it at Amazon. It will answer most of the basic questions and it has photos of parts and contact info for vendors.

, this book is a good starting point, and then you can ask for second opinions, and make your own informed choices.

If'n I was you...

I'd do some research...

For a frame of reference my current daily driver is.

2002 Mustang
Maximum motorsports
Caster camber plates
tubular K frame
Tubular control arms
Adjustable aluminum rack bushings
Adjustable tie rods (bumpsteer kit) with spindles drilled for bolt through instead of taperd studs.
Full length frame connectors
pan hard bar
converted to torque arm so I could ditch rear upper control arms.
Rear tubular lower control arms
Rear solid cobra swaybar
Shorter front poly sway bar links

MM custom valved Bilsteins shocks and struts.
375# front coil over springs so wheel rate is 337.5
225# rear coil over springs so wheel rate of 245.5
Lowered 1.25 inches front between 3/4-1 inch back sacrificing a little bit of handling for a subtle rake.

2004 cobra brake upgrade


My 2 complaints about that car are

1. While the cobra brakes are good I would like to stop a little better.
2. If I had to do it again I would probably go a little softer and use regular bilstein HDs instead of the custom valved so I could back a few pounds off on the springs. Car corners great but could do a little better on comfort.

I would like the 71sat to be more comfortable.
I have no intention of trying to be competitive with the 71 sat.
My goal is a precise feel, no slop, corners well while still being comfortable and future serviceability.
I think I 'm having the most trouble because every time I try to find a set up its.

XXX only works with XXX mounted calipers.

Caliper XXX won't work with XXXX sway bar.

Steering box a won't work with coupler b. etc

Places give wheel rates for torsion bars, but just generic listings for leafs (stock,hd) making it hard to match front to back.

For the brakes, consider pressure and booster requirements. I run the Cobra style on a '70E with EBC yellowstuff pads... works great and needed a double 8" booster and 15/16" master for adequate line pressure. I don't know piston area on the Brembos. It all fits under 17" wheels.

As far as rear springs, in round numbers stock low po are 120#/inch, MOPAR XHD are 140#/inch and XHD+full added leaf are 170#/in. I'm running the XHD+1 leaf. The added leaf corrected the sag as the springs aged and got the rate where I wanted it.

[quote=71sat440]

Right now I'm set towards the doctor diff brembo style front and cobra style rear brakes.

I had dr diff old 13" kit and I had to go to 18" rims


Will these eliminate any type of sway bar choices.

No


Sway bars, my lower control arms have no mounting brackets, does anyone sell the brackets so i can weld them on or am I just better off finding a set with them and rebuilding them?



I believe firm feel and hotchkis sell these



Or do they have aftermarket set ups that bolt on different?


Same



Wheel rates how hard is it going to be to match a good set between the front torsion bars and rear springs?

Companies like firm feel and hotchkis and xv ect. Have done this testing already so u dont have to.



Steering, not real fond of the factory box and would like something a bit more responsive.

What are your suggestions.


Firm feel stage 3. The boregson is a hit or miss right now and a expensive one at that.

Also pick up andys book mopar bbody performance upgrade 1962-79
[\quote]

As Dangina said, we have spent a lot of time developing our system to balance sway rates, spring rates and our valved shocks to produce the most competitive system on the market for Mopars right now. If you have any questions, feel free to give us a call or check us out! www.hotchkis.net

Which book is that?

Those Mustang wheels aren't going to work. That's what I used for my mock-up wheel and they were rubbing the calipers.

I beleive he's talking about this one. http://smile.amazon.com/B-Body-Performan...y+f+b+body+book

Thanks for the heads up, might go with just the cobra upgrade after all.
I'm familiar with the system, parts availability is wide.

Might just keep it simple with a firm feel 3 box, re informed k member. 1.12 t bars and springs with blisters and doctor diff cobra brakes front and back and some frame connectors.

Who has some good connectors? I see the ones that follow the floor pans on both UScartool and XV but I remember some drama for both on moparts.

Also does anyone know if firm feel brings stuff to carlisle so you can save on shipping and core charges?

That's one of the books I have.
It's a good read.

Just as an FYI, we've been running some pretty good show specials this year. 25% off list price/no tax/free shipping if you buy at the show and we'll be at Carlisle... Just saying...

I haven't seen Firm Feel in years at Carlisle. It would be a long round trip for them. i also understand Mancini has dropped out of attending, which I don't understand, but if they have enough money, great.

This^^^^^, great business technique, get out and meet people,show your junk, sell it and help cover the costs of playing all at the same time. Good stuff!

i used torque boxes from these guys:

https://www.autorust.com/product-category/mopar/mopar-b-body/

I've had no problems with them but I have heard df drama from them before, On a side note alot of this stuff can be made by you, for the inner fender braces and lower rad brace I went to a shop that builds cages and had them bend me up some DOM. Costs way less.

Just ordered one.

These are spring rates. To find the actual wheel rate, you will have to calculate the motion ratio then multiply that by the spring rate. Additionally, if you are putting a sway bar into the equation, its applied rate and related motion ratio adjustment must be factored and then added to the leaf springs to come up with the total wheel rate.

There are enough variable in the set of calculations for the above pieces not to mention the variety of different sway bar mounting methods, wheel offsets, and spring locations for the actual rear wheel rate to be somewhere between 80-300# without any set standard.

You lost me, how/why do you figure a motion rate on a live axle leaf spring set-up? I thought motion/spring rate are the same?

Leaf spring width center to center divided by contact patch center to center produces the live axle motion ratio. Anti-roll bar mounting locations will also have a motion ratio associated with their mounting points on the axle housing as well. Although most changes are pretty miniscule and will have minimal impact, its nice to verify.

For example, IIRC, moving springs inboard 3", a common mod for larger tires, alters wheel rate around 30#. Putting wider rims on with minimal backspace could move the contact patch out 3-4 inches as well. All these ratios and mounting datums is how a 1" diameter, under axle, rear sway bar can have a nearly identical applied rate at the tire to a 3/4" above axle mounted bar in an OEM locations on the housing. Widely divergent bars rats equaled out by motion ratios and lever arms.

Ain't geometry fun!

So to the OPs stated wheel rates in the street Mustang that you are trying to emulate in your '71, how inclusive are those rates in your 'stang, because if those are just the wheels rates of the springs, you have a whole 'nuther set of calcs to perform.

I thought we were talking leaf spring rates rather roll rates, nevermind.

The place I buy my stuff from (Maximum motorsports)

Has a formula to figure out stock spring rate vs wheel rate.
Front wheel rate is 25% of spring rate. So an 800# spring has roughly a 200# wheel rate.

Once you move to a coil over because to the location of the spring changes among other things it becomes 90% so 800# spring rate becomes 720 wheel rate.

The rears are much closer being 50%
So a 800# spring would be 400 wheel rate

Change to a coil over and it becomes 110% because the spring gets moved behind the rear axle.
So 800# spring becomes 880 wheel rate.

I just used made up round numbers but you get the idea.
I'm sure those are basic numbers considering all else is relatively stock.

I was trying to see if there was such a formula for the torsion bars and springs.

They got me real close to what I wanted. They warned me about the slightly harsher ride and actually told me to use bilstein HDs and not their custom valved.

But the custom valved struts have reinforced ears to prevent bending under hard cornering and the top is shaved for a perfect seat of the coil over perch vs just sitting the perch on a weld for the HDs and I really wanted those benefits.

Car handles amazing, I can still make it slide if I push hard, but I'm surprised by what it takes.

But take it over train tracks or some of the PA potholes were known for and you feel every.......little..........thing.

Think of it this way I'll use my mustang as an example.

The spring is really close to the frame stock.

A coil over spring puts the spring way out by the wheel.

From a lever stand point it takes a lot less force having the lever out at the wheel (coil over) then closer to the bottom of the lever (control arm mount) where the factory spring is.

So 2 springs that are the same spring rate have much different wheel rates just by changing the location.

So the wheel rate is actually a more important and accurate figure.

Obviously I'm not changing the location of the front t bars or rear springs, but if you can figure out wheel rates of t bars and springs it can help you get a closer balance between the front and back of the car.

Wheel rate and spring rate for a Mopar torsion bar setup is the same.

Leaf spring is not, you need to measure and do some calculations to figure it out.

http://www.speed-wiz.com/calculations/suspension/suspension-weights-calculation.htm

"Front wheel rate is 25% of spring rate. So an 800# spring has roughly a 200# wheel rate."

This I gotta see.

Maybe this one would be better?

http://www.speed-wiz.com/calculations/suspension/leaf-spring-calculation.htm

It however as I see it, assumes a symmetrical leaf spring, and our Mopars are not so equipped.

Like I said its all about leverage.

Go put a breaker bar with a socket on one of your wheel nuts.

next try taking the stud off with your hand right next to the wheel nut.

then try to take one off with your hand at the end of the breaker bar.

My factory spring rate was 450# my coil over spring is 375#

So basically my old wheel rate was around 180, my coil over wheel rate is about 280 so my much softer coil over spring gives me a much stiffer ride do to having way more leverage out at the wheel vs right where the control arm bolt to the car.

And while the calculator you provided will help determine spring rates of leaf springs, you need to know what the formula is to convert that to a wheel rate to be more helpful when trying to set up a car.

Yeah, I got a little carried away. I think I lost everyone else in the tirade as well.



Okay, so you only want the sprung wheel rate. Very simple. As pointed out above, mopar torsion bars are mounted at the pivot point so their ratio is 1:1. A 300# t-bar is a 300# wheel rate. Go to Firm Feel to look up rates and you'll find that 1" bar is 175# and a 1.06 is 225#

Out back, you need to do some measuring to arrive at the rate. Taking a swag at it with info in the tech archives here on moparts, spring pad mount center to center on your '71 is 47.3". Your flange to flange measurement is 57.8". This is assuming you have a zero offset rim that doesn't offset the tread at all from the flange face, your motion ratio on the rear is .82. If you have original style, XHD springs that are approximately 160# spring rate, you have roughly 130# wheel rate on the rear.

But as jcc pointed out there are sprung wheel rates, roll rates, and total combined rates. It sounds like your Mustang could use a little softening of the spring rates with a corresponding step up in roll rates to maintain its handling characteristics while softening its ride.

Unfortunately for your Mopar, no one has a calculator to quickly whip up the roll rates and combine them into your total rates. Additionally, because of wheelbase and total weight and distributed weight differences, you may not want to identically duplicate your Mustangs rates to a tee.

This is what I was trying to point out in my earlier post. Wheel rates are a great barometer to measure unlike suspensions against each other, but there are a lot of other variables to consider in creating the total package, not the least of which is weight distribution which will determine how much resistance is needed on each end. This is part of the reason your Mopar can get away with a much softer rear rate than your Mustang.

If you want to get into the analysis of your specific system, you need to know total weight and distributed weight to get in the ball park of roll couple you need. Once you have that, you need roll rates of various sway bars to pick a combination for the front that will support the requirement. After you know that, then you need to back into the rates needed on the rear. The reason behind this approach is because there are only so many off the shelf t-bar and s-bar combinations for the front, but there are almost unlimited leaf spring rates than can be created.

The simplest answers are to either call Firm Feel and go with their recommendations or pick up a Hotchkis package. The next simplest method is to use the formulas in Andy's book to get in the ball park of what you want.

BMW 3 series have a similar arrangement on their rear suspensions. They use some outrageously large spring rates to achieve some moderate wheel rates.



True, but it is still germain because of the long, softer rear segment of the Mopar leaf set up retains similar spring characteristics. If you want to get real deep into leaf spring calculations, you also have to consider camber, load, and checking rates in addition to the spring rates and their impact on overall design. The asymmetrical set up of the Mopar spring also creates a different control ratio which will have an impact on anti-squat calculations that are significantly different from a symmetrical set up.

Thanks for all the replies.

Just ordered Andys book, was waiting of my Amazon CC statement to use points to pay for it :P

I spent a ton of time looking for answers when I did my Mustang and thats a very easy car compared to a t bar/leaf setup. Especially since you didn't have to worry about things like weight difference between small block and big block.

I have a tendency to snowball projects and I'm trying to keep it simple.

Did a preliminary wish list yesterday and hit 4k before I even adresed the brakes.

And the sat is the car I want more for comfort. My demon is then I want for cornering.

Hopefully I'll learn a lot on this car and be able to apply it to that one.

"I have a tendency to snowball projects and I'm trying to keep it simple."

You are preaching to the choir.

I quote a a time honor race car saying:

"Everything effects everything else"