Leaf springs for handling

[4406bbl]

The problem with hd mopar springs for an e-body is left and right are very different, the left side second leaf is short, and does not support under the spring eye like the right, side leading to wheel hop. B and E hp rear springs are way different from each other, stock 340 springs are a disaster with power in a handling car because the second leaf is short, wheel hop city. If you go mopar maybe use 2 right side go springs so both are the same, with the longer second leaf, and dump your money into the best rear shocks you can get. I think hotchkis uses a thicker main leaf to combat the wheel hop issue, mopar b-bodies did it with more and longer lower leafs.

 

[Superbeemike]

@Superbeemike - I just read your thread, great read and again awesome car. I appreciate you posting on this thread. When I finally get a chance to build this car I will start a build thread on it. I am looking forward to it. My Cuda is radically done with a 4 link, Viper front brakes, full bracing, etc. but i have not had a chance to track it yet.

No problem. I’d love to see the build and I highly recommend taking it out to a track day when you finish. It’s gotta be the most fun I’ve ever had with a car, and I have quite the resume.

 

[Jonas Nordstrom]

Ive got Eaton HD springs (7 pass, 6 driver) original height + Hotchkis rear sway bar set on hardest.
Rubber bushing on front eye, Polys for the rear eye.
Couldnt be happier.

 

[70chall440]

The problem with hd mopar springs for an e-body is left and right are very different, the left side second leaf is short, and does not support under the spring eye like the right, side leading to wheel hop. B and E hp rear springs are way different from each other, stock 340 springs are a disaster with power in a handling car because the second leaf is short, wheel hop city. If you go mopar maybe use 2 right side go springs so both are the same, with the longer second leaf, and dump your money into the best rear shocks you can get. I think hotchkis uses a thicker main leaf to combat the wheel hop issue, mopar b-bodies did it with more and longer lower leafs.

I have a variety of springs (B body) to choose from currently and I will take some time to really look at the spring design. I am thinking that I might be able to "modify" some springs to get what I am after. As to the shocks I just ordered a complete set of QA1 single adjustable yesterday.

 

[70chall440]

I'm also interested in this, I have stock/worn out everything small block/auto with intentions of 440/727 swap pro touring style build. Trying to buy one time, would like it to be balanced front to rear, using T-bars and leafs.

So far here is my take away on all of this, while there are many choices on the market it would seem that there really isn't any reason to spend $700+ on a set of springs when you can either use what you or purchase something like the Mopar springs or ESPO (which have a good rep). After thinking about it I do not think I would get a lowered spring (say -1"), rather I would use a 1" lowering block. My reasoning is that by going to the -1 springs you (I) am limiting my options in that I cannot raise the car easily with those springs without using longer shackles and adjustable front hanger both of which would not be beneficial to handling really (IMO) whereas if I were to go with stock and use a block, if they ever sagged I can just remove the blocks.

I also believe that for handling you need 3 more things; good - great shocks (this is where the real expenditure needs to happen), large sway bar, and good tires. So I have decided that at least for me I am going to use the following;

Stock springs (at least for mock up, if they are bad I will get new Mopar or ESPO springs)
Hotchkiss or maybe a Firm Feel HD sway bar (HK is 1" Firm Feel is 7/8)
Wheels and tires remain an unknown but I would like to go no more than 17" and use a steel wheel with the stock Dodge hubcaps (I like the look and there is a company that makes these wheels). I am thinking 17" because I am going to be running large disc brakes and a hydroboost system (bought some 2018 Shelby Mustang GT500 calipers).

In the front I will be running at least 1.14" T bars (Firm Feel), large sway bar (probably Hotchkiss), reinforced LCAs, Firm Feel tubular UCA (they offer more adjustment in the design over stock), fast ratio pitman/idler arms, Borgeson PS box, poly bushings, adjustable struts and a reinforced K frame.

I am also going to have full vehicle bracing; USCT sub frame connectors, torque boxes (I will make), under fender braces (I will make), radiator core support brace (I will make) plus I am considering developing an upper shock tower brace (still thinking about this).

My hope is that this set up will yield a car that handles well yet rides ok (less concerned with the ride but doing want it to be an issue).

 

[440 PHIXX]

They’re buggy springs with a straight axle. The design goes back to the mid 1800’s. Not the best design for handling and cornering. Luckily, I like go fast in a straight line.

 

[70chall440]

Yeah thats true but I know that you can get a leaf spring car to handle relatively well within the constraints of having a solid rear axle. It is what it is but I am confident will be fine for what I am doing. Going fast in a straight line is fine if thats what floats your boat but unfortunately most real roads have turns and curves so it would be very helpful to be able to deal with this in a controllable manner.

 

[440 PHIXX]

Three things help immensely... lowering unsprung weight, lower profile tires, and a rear anti-sway bar.

 

[70chall440]

Three things help immensely... lowering unsprung weight, lower profile tires, and a rear anti-sway bar.

Yep got that and have a plan to address all of them, in fact I am looking at various rear sway bars right now.

 

[Cranky]

How much wider were the E bodies at the rear?

Don't remember off the top of my head but when I was building a 70 Barracuda bracket car, I moved the front spring hanger all the way in and against the frame rail. IIRC, that was 1.5" and had to make offset spring hangers that were 2.5" just to make the springs parallel for tire clearance that was the same both front and rear of the tire. If you have an E body you can confirm the distance between the front hanger and frame rail. My 66 Belvedere's front spring hanger is 1" and is closer than the E body hanger. And in case you're wondering....I drilled an access hole through the rail to install the spring eye bolt. And then spring hanger interfered with the rear pan. Didn't even think about that but a glass pan would have been easy enough to modify.

 

[Sweet5ltr]

So far here is my take away on all of this, while there are many choices on the market it would seem that there really isn't any reason to spend $700+ on a set of springs when you can either use what you or purchase something like the Mopar springs or ESPO (which have a good rep). After thinking about it I do not think I would get a lowered spring (say -1"), rather I would use a 1" lowering block. My reasoning is that by going to the -1 springs you (I) am limiting my options in that I cannot raise the car easily with those springs without using longer shackles and adjustable front hanger both of which would not be beneficial to handling really (IMO) whereas if I were to go with stock and use a block, if they ever sagged I can just remove the blocks.

I also believe that for handling you need 3 more things; good - great shocks (this is where the real expenditure needs to happen), large sway bar, and good tires. So I have decided that at least for me I am going to use the following;

Stock springs (at least for mock up, if they are bad I will get new Mopar or ESPO springs)
Hotchkiss or maybe a Firm Feel HD sway bar (HK is 1" Firm Feel is 7/8)
Wheels and tires remain an unknown but I would like to go no more than 17" and use a steel wheel with the stock Dodge hubcaps (I like the look and there is a company that makes these wheels). I am thinking 17" because I am going to be running large disc brakes and a hydroboost system (bought some 2018 Shelby Mustang GT500 calipers).

In the front I will be running at least 1.14" T bars (Firm Feel), large sway bar (probably Hotchkiss), reinforced LCAs, Firm Feel tubular UCA (they offer more adjustment in the design over stock), fast ratio pitman/idler arms, Borgeson PS box, poly bushings, adjustable struts and a reinforced K frame.

I am also going to have full vehicle bracing; USCT sub frame connectors, torque boxes (I will make), under fender braces (I will make), radiator core support brace (I will make) plus I am considering developing an upper shock tower brace (still thinking about this).

My hope is that this set up will yield a car that handles well yet rides ok (less concerned with the ride but doing want it to be an issue).

You're definitely on the right track. Frame Connectors, F&R Swaybars, Torsion Bars, & Hotchkis (FOX) shocks and these cars will actually take a corner at speed. Quick ratio steering box wouldn't be a bad idea as well. Don't forget the alignment differences with modern radials, compared to vintage bias-ply tires.

 

[70chall440]

You're definitely on the right track. Frame Connectors, F&R Swaybars, Torsion Bars, & Hotchkis (FOX) shocks and these cars will actually take a corner at speed. Quick ratio steering box wouldn't be a bad idea as well. Don't forget the alignment differences with modern radials, compared to vintage bias-ply tires.

View attachment 1186039

Yeah I agree, I will be using a Borgeson box with fast ratio pitman/idler arm. I do my own alignments so thats not an issue. Not sure what wheels and tires I will be using until I get the mock up done specifically with the brakes.

 

[70chall440]

So as I am apt to do I began researching leaf springs in depth. I have a set of Hotchkis springs here for a build I will be doing on a friends car and I have a set of stock springs (71 Charger) as well as SS springs under a 70 Satellite that is in my shop and factory springs under my 70 Challenger RT (440).

Hotchkis said at one time that their springs are "geometry corrected" (notice they don't say that now EDIT: actually do if you find the right web page). There are definitely differences in their spring pack but I cannot see any "magic" that would make their springs necessarily any better than anything else other than that they have multiple short leaves in the front of the pack somewhat similar to SS springs.

Now I stumbled upon Global West and they are promoting reverse eyelets and spherical bushings. The reverse eyelet seems to make some sense but the spherical bushings have me scratching my head a bit. I understand the concept but I guess I would have to see some modeling to fully get my head around it.

I am really trying to determine what makes for a good/great handling system as it relates specifically to the springs. From what I am seeing/reading it would seem that so long as the springs are in working condition, are somewhat stiff in the front pack to resist axle wrap AND are supported by a good sway bar and good shocks you are as good as you are going to get.

I realize that "handling" is a broad based term and encompasses an entire system which includes body stiffness, reduction of unnecessary movement throughout the system, quality components, stiff sway bars and minimization of axle wrap (and of course good tires which have a good contact patch). All this leads me to believe that while some springs are better than others from a stiffness standpoint, they unto themselves are not the "magic bullet" as some would like you to believe.

To this end and looking at the Hotchkis springs, I believe they can be easily replicated using a couple of sets of older springs (assuming you have some which I do). However if you don't have them, then you could purchase pretty much any good spring set and be at the same place. In other words there is no reason to spend $700 on a set of "performance" springs when you can get the same effect for $300 or perhaps less.

Sorry for the rant and long post but I know there are a lot of people out there who are wondering the same thing. I ordered the book "how to make your muscle car handle" so I will see what they say but in thinking through this, I think I am on track (no pun intended).

 

[ckessel]

Try these guys too.Landrum Performance Springs | Mentone, INhttps://landrumspring.com

 

[70chall440]

Thanks, I looked at this website previously. So the question is "what makes any spring a performance spring?" In this case they have mono springs and multi leaf springs, why would you use one over the other? I can hazard a guess from my own experiences but I know that 1st Gen GM F body (Camaro/firebird) guys frequently ditch the mono leaf spring in favor for multi leaves.

 

[Cranky]

Thanks, I looked at this website previously. So the question is "what makes any spring a performance spring?" In this case they have mono springs and multi leaf springs, why would you use one over the other? I can hazard a guess from my own experiences but I know that 1st Gen GM F body (Camaro/firebird) guys frequently ditch the mono leaf spring in favor for multi leaves.

If you have access to other than stock springs, measure the thickness of each individual leaf. Even stock spring leafs can differ and it's a pita for sure but that's one way to see what's going on. Also, a leaf that's say 3/16'ths thick might not have the same PSI per foot as another same size leaf. I'm sure you know that cars with 'soft' springs and large bars and good shocks can handle well too. I've done 'some' autocross but learned a lot in my limited experience in doing that. Playing 'games' with the street guys was also fun when doing the bias stuff.....such as having larger diameter tires on one side than the other when most of the turns were all lefts vs right. I do enjoy beating them with a 66 Belvedere

 

[Photon440]

This book (which I admit that I haven't opened in years) said that the best lateral handling was with the leaf springs flat - no arch when loaded.

 

[66Satellite47]

Not sure what application you are going for. A drag racing application is sure not the same as a touring car. My experience is with making drag race spring combo's. A road course car will need something different than what I have built. The GM stuff generally had very different set up's for road racing than drag racing. The Ford road race stuff was also very different.
I played a lot with leafs for my '65 Coronet drag car, found something real close to the Mopar SS springs that worked great. I bet a cornering car will will want a more even spring set than a drag race combo.

 

[Cranky]

This book (which I admit that I haven't opened in years) said that the best lateral handling was with the leaf springs flat - no arch when loaded.
View attachment 1189068

Been there done that!! Just because a leaf spring looks flat doesn't mean it's junk.....but that usually means it is with a stock leaf spring. But even with a stock 'flat' spring doesn't mean it won't handle well with the right SB's and shocks. Only way to know is to try it......

 

[70chall440]

What I am after is a very good handling car, not necessarily a road race or even a autocross racer (although I certainly would autocross it if I get the chance), that said this has now turned into more of a research project overall, more for my own information and those who might read this thread.

I (like many) know how to get a car to handle "relatively" well for the street and perhaps some spirited driving (good front end components, good alignment, chassis stiffening, sway bars front and rear, decent sized T bars, wider/sticker tires, etc.) however what is pushing me at this stage is trying to understand what i will call "the truth" to this issue of handling.

I know that there are MANY variables at play here and there is no 1 answer, but I feel like there are some basic rules and guidelines that will yield a better than stock handling vehicle. Again, the list above is a pretty good "snap shot" of making a Mopar handle, but I am trying to drill down on the actual components, in this case the rear leaf springs.

I guess what I am really trying to get my head around is this;

1. Are some leaf spring designed better than others (as it relates to vintage/Muscle cars)? If the answer is "yes" then what makes them better (beyond the marketing) and how much better are they? Its fine to say something is "better" but if the degree of improvement is not something the driver will ever notice or be able to use then it is of little use.

2. Hand in hand with the #1, why are some springs $700+ and others $300 or less aside from marketing and brand name; in other words is a $700 set of springs twice + better than a $300 set of springs?