Register now to get rid of these ads!

Technical Hot Rod Anti-sway Bars

Discussion in 'Traditional Hot Rods' started by JSchmitz67, Aug 10, 2026.

  1. JSchmitz67
    Joined: Feb 22, 2026
    Posts: 54

    JSchmitz67
    Member
    from Union, MO

    I'm building a '32 Chevy 5-window. I'm wondering if anyone has put anti-sway bars on a similar car. Is it even necessary with such a light vehicle? I know it's not going to be a sports car. This is my first Hot Rod. How bad is the body roll? I'm thinking I can make them sorta hidden.
     
  2. Tim
    Joined: Mar 2, 2001
    Posts: 21,548

    Tim
    Member
    from KCMO

    Widely available but generally not needed if everything else is set up properly
     
  3. Jimmy
    Joined: Dec 11, 2002
    Posts: 531

    Jimmy
    Member

    I had a 1930 Chevy with early (no sway bar) Corvair front suspension and stock-type parallel leaves in the rear. It handled just fine. there was some lean but nothing that I felt was excessive. Good luck with your project.
     
  4. DDDenny
    Joined: Feb 6, 2015
    Posts: 23,417

    DDDenny
    Member
    from oregon

    Those ol Chivolets had a lot of wood inner body structure, not a lot of support if the wood is questionable (or missing), that, and the cars'original frame rails and its near hundred years of abuse that no doubt is showing its age should be a consideration before doing what you are proposing.
    Also, the section of the frame rails where an anti-sway bar would be mounted should be boxed, otherwise not much is accomplished by adding a bar.
     
  5. willymakeit
    Joined: Apr 13, 2009
    Posts: 1,503

    willymakeit
    Member

    Different opinion but
    I put them on my 56 F100 with I-beam axle. Made a great improvement in body roll with good shocks.
    This was front and rear with bigger bar on front.
    All of it got me to within 75% of a ifs.
     
    Blade58 and Sharpone like this.
  6. There's a lot of variables on sway bars. The type of suspension you have makes a difference, as well as vehicle weight, tires and spring rates. Generally speaking, if running an early Ford type suspension with transverse leafs and split wishbones, no bars are needed as the axles perform that function. You will however sometimes find track bars to remove the 'slop' in the shackles on both ends of the spring. 4-bars won't offer quite as much '***ist' but in most cases will be enough. Parallel leafs are also less likely to need them, although if leafs are removed for a softer ride sway bars can restore flatter cornering with little penalty in ride quality. Coil suspensions are usually where you'll find factory front sway bars, but again, vehicle weight and spring rates make a difference. Rear bars are usually only used when looking for as much cornering power as possible, although GM used them on their trucks with coil rears until they finally switched back to leafs to prevent excessive sway. You'll find rear bars under a lot of late-model SUVs for the same reason.

    IIRC, Hot Rod ran a series in the late '70s on improving handling, showcasing the two main schools of thought at the time. **** Guilstrand was a stiff spring/small or no bar advocate, Herb Adams preferred soft springs and big bars. Guilstrand turned in a bit quicker lap times at Willow Springs raceway, but the cost was a harsh ride. Adams' cars weren't quite as quick but were much easier to live with.

    A front bar can improve the handling of nearly any car, but it's up to you to decide if you need it. My avatar lacks a front bar and while the handling is 'acceptable' (M2), one of these days I'm going to add one.
     
  7. JSchmitz67
    Joined: Feb 22, 2026
    Posts: 54

    JSchmitz67
    Member
    from Union, MO

    All good input. I guess I'll wait and see how much body roll it gets. Light body cars should get less IMHO. lol! I'm running factory frame and parallel leaf springs. The frame will be mostly boxed end to end.

    I did read an article about the different schools of thought between Guilstrand and Adams. Good stuff!
     
  8. Kerrynzl
    Joined: Jun 20, 2010
    Posts: 3,657

    Kerrynzl
    Member

    If you like a soft ride ,then yes the car will benefit from sway bars.
     
    Ned Ludd likes this.
  9. Joe H
    Joined: Feb 10, 2008
    Posts: 2,057

    Joe H
    Member

    I put one on the front of '37 Chevy truck, it sets fairly high, so the bar made a big difference in how I drive it now. It had a pretty good lean in corners with four soft leaf springs. Mine is around 3300 lbs split 50/50 front to back.
     
    JSchmitz67 and Blade58 like this.
  10. Blade58
    Joined: Mar 5, 2012
    Posts: 378

    Blade58
    Member
    from apopka ,Fl

    I have it on my 38, with tight rear wheel clearnce it makes a differnce on body roll
     
    JSchmitz67 likes this.
  11. mohr hp
    Joined: Nov 18, 2009
    Posts: 1,908

    mohr hp
    Member
    from Georgia

    I read a lot of old car related stuff. I have found several writers (Gray Baskerville being one) used the term "sway bar" in place of the word "panhard bar" in the 70's. Whether you need or want one is probably up to you. They definitely can help with body roll, since pre war cars were not engineered to live at 75 MPH. I'd say get it on the road and see how it drives first.
     
    JSchmitz67 and GuyW like this.
  12. dan c
    Joined: Jan 30, 2012
    Posts: 2,680

    dan c
    ALLIANCE MEMBER

    i've messed with sway bars and have had good results on a pickup. i think you should be o.k. with one on the front, but if you don't have a matched sway bar for the back, you'll encounter over- or under-steer.
     
  13. Rear bars were rarely used in OEM applications up until the 2000s, usually only on performance versions. Front bars however were standard equipment on nearly all coil-sprung independent car front suspensions starting in the late '40s, but were generally rather small, usually in the .5 to .75 inch range. Trucks not so much as most had higher spring rates, and generally none were fitted to parallel leaf-spring suspensions.

    A key thing to remember is nearly all p***enger vehicles were sold with considerable designed-in understeer for safety reasons, the few exceptions being some sports cars and/or mid or rear engine models. A vehicle with oversteer will swap ends when you reach its limit, not a good thing. A front bar can reduce that understeer up to a point (generally traction limits), but go too large and now you need a rear bar to offset it. Go too large on a rear compared to the front and you get oversteer.

    As I seriously doubt you'll find an aftermarket bar for your stock suspension, getting a copy of Herb Adams book should give you guidance in selecting a size. Then it's just a matter of finding something that fits with some adapting.

    https://www.betterworldbooks.com/pr...MI94GNm56ZlgMVtCytBh36HBdAEAQYAyABEgKpGfD_BwE

    I will throw this out for general knowledge. Most factory bars are installed on the ch***is, with the end links connected to the suspended part (control arm or axle). But a lot of the aftermarket rear bars are backwards from this; the bar is attached to the axle housing, the ends links to the frame. Not all housings will tolerate this. Speaking specifically to Ford 9" housings, some are too light for this and the action of the bar will bend it, drastically shortening axle bearing life. I learned this the hard way. This is primarily an issue with leaf-spring car housings. Truck and coil spring housings don't seem to be a problem. If you do mount the bar to the axle housing, get the mounting points as close to spring pads as possible. The one I had issues with put those about 5" inboard of the spring pads.
     
    Just Gary, JSchmitz67 and 05snopro440 like this.
  14. gimpyshotrods
    Joined: May 20, 2009
    Posts: 24,629

    gimpyshotrods
    ALLIANCE MEMBER

    A whole lot of early cars had a frame that acted as a suspension element. It was expected to flex, when the suspension reached the end of its flexibility.

    That is just what you would need on a rutted dirt 1932 country road, at 20mph.

    That is exactly what you do not need or want on pavement, at anywhere near highway speeds.

    The first order of business is boxing the entire frame, and or reinforcing it, in the case of later top-hat style frames.

    Then, if there are issues, you can look into a front bar.

    As has been mentioned, a rear bar can be trouble if it is not the correct one. That said, every single one of my vehicles has a rear bar (except the motorcycle). All of those are custom-made to the correct rate for the vehicle.
     
    Ned Ludd, Just Gary, rockable and 3 others like this.
  15. JSchmitz67
    Joined: Feb 22, 2026
    Posts: 54

    JSchmitz67
    Member
    from Union, MO

  16. JSchmitz67
    Joined: Feb 22, 2026
    Posts: 54

    JSchmitz67
    Member
    from Union, MO

  17. jnaki
    Joined: Jan 1, 2015
    Posts: 12,052

    jnaki

    upload_2026-8-13_4-0-51.png

    Hello,

    When my wife and I got our 327 powered 1940 Ford Sedan Delivery project, it handled just awful. Shakes and pulls to right on the freeway. It also did not stop well and when we went around couners, there was a slight “klunk.”

    So, that was not how our sedan delivery should sound. We tried repairs first as what we could do. Not a fix as everything did the same. Then we replaced some components and that sort of helped. Remove lever shocks and put in tube shocks.

    Finally, we took the sedan delivery to a friend who had just moved his whole wheel/tire/alignment shop from west Los Angeles to orange county. Now, instead of around 60 miles one way, which we had been doing for all of our family cars: Olds, Impala, Buick, Flathead sedan delivery and various VW vans.

    His shop was about 20 miles away but, it was like night and day.
    upload_2026-8-13_4-1-42.png
    My friend looked at the front end and then took it for a drive. he pointed out the problems and said there is a way to fix all of them. So, back at his new shop, he took the whole front end apart. Old parts out and new parts in place, correctly. After he put in most of the new replacement parts, he did some adjustments and took it for another drive. Finally, he put the front sway bar back in place.

    He remembered his first drive with the sway bar in place. Not good, but the sway bar did its job of keeping the sedan delivery level when going around corners, or at least some resemblance of level.

    Now, that he had put on new tube shocks, it started to handle like a new hot rod should. Grip comes from new tires, straight line driving came from new front end components. A good wheel balance, alignment and one final road test proved the out with the old and in with the new. Including the front sway bar. It cornered well, felt good in a straight line drive and “no sway” during high speed freeway or open road drives… YES!

    Jnaki

    The sedan delivery handled, stopped and took off with a flourish, so well that my wife made it her daily driver and it was hard to grab the keys first. YRMV
    upload_2026-8-13_4-2-31.png

     
    JSchmitz67 likes this.
  18. willys36
    Joined: May 6, 2006
    Posts: 3,459

    willys36
    Member

    I put rear sway bars on several cars with good results. A '37 Willys pickup, my '36 Willys coupe and a '36 Pontiac sedan that had the knee action independent front which I replaced with a MII (read quickly . . .mentioning a MII front end gets posts eliminate quickly from HAMB!!). The Pontiac is likely very similar to your Chevy.

    I used Ford Courier pickup front bars which are perfect for pre-war cars, near the right width, 3/4" or 7/8" diameter. The ends of the bar flare out but I had no problem bending them to the right width on my 12 ton Harbor Freight press. I got all the hardware from the pickup - rubber bushings, brackets long bolts etc., but those can be made if the originals aren't in good shape. Killer is, they are old obsolete trucks and the likelihood of finding one in a junkyard nowadays is nil.
    My '36 Willys. You can sort of see the ends of the bar in front of the crossmember and axle. Sort of!! I welded in a big '56 Olds ( had it lying around) crossmember to mount the bar and stiffen the frame a bit.
    Under ca1r.jpg

    The '37 Willys pickup. Don't have photos of the rear Courier bar but we adapted a MII bar on the front which had a MII grafted on.
    tilt closeup.jpg

    Here is the '36 Pontiac sedan showing the Courier bar fairly clearly. End bent in slightly to fit the For 7". It also jad a MII to replace the factory knee action abortion with the MII sway bar. I think I welded in a 2"x2" square tubing crossmember in front of the axle to mount the bar.
    pontiac_2..JPG
     
  19. Andy
    Joined: Nov 17, 2002
    Posts: 5,480

    Andy
    Member

    I have used a rear sway bar on my roadster for years. I found that the car understeered terribly with the weight forward and the bigger tires in the back. I have made ones with different diameter bars. Every time I change tires I have to make a new bar. The bars are just mild steel. All steel has the same stiffness. High strength steel just lets it bend further with out yielding.
    I have coil overs on the back. The rate is only 125. I made fittings that attach to the shock bolts for the links to the bars. I am running a 7/8” bar now with 8” arms.
    It is easy to check roll stiffness. Jack up the car one end at a time with the jack right in the middle of the axle. I sit in the doorway and measure to the floor with and without sitting.
     
    JSchmitz67 likes this.
  20. cfmvw
    Joined: Aug 24, 2015
    Posts: 1,288

    cfmvw
    Member

    This thread brings back some memories. I used to scrounge through the junkyards with a tape measure and calipers looking under different cars for various sway bars that would fit under my cars to tune the ride and handling. Even some of my OT daily drivers got factory sway bar upgrades from their performance offerings that I came across while hunting through the junkyards looking for project parts.
     
    JSchmitz67 likes this.
  21. Doublepumper
    Joined: Jun 26, 2016
    Posts: 1,996

    Doublepumper
    Member
    from OR-WA, USA

    My '46 pickup was a boat without some type of stabilizer. Put a bar on the front and used the third shock setup from an Explorer on the rear. Really helped in controlling front dive in turns and body roll. Truck handles like a new one now and is very stable.
     
    JSchmitz67 likes this.
  22. THE FRENCHTOWN FLYER
    Joined: Jun 6, 2007
    Posts: 6,295

    THE FRENCHTOWN FLYER
    Member
    from FRENCHTOWN

    I copied this from my Attic Anglia build project. I dealt with Fatman (RIP) tech guys regarding sway bars on my Anglia build:
    Another thing that I liked: when I ordered the kit I told them to include a front sway (anti-roll) bar kit. They told me one would not be needed for my application - only one was needed at the rear of the car. Well, he could have sold me an unnecessary kit and increased his profit and I'd have been none the wiser.
     
    JSchmitz67 likes this.
  23. Bandit Billy
    Joined: Sep 16, 2014
    Posts: 17,190

    Bandit Billy
    ALLIANCE MEMBER

    Nice T/A Snowflakes!
     
  24. Rodney Dangercar
    Joined: May 19, 2024
    Posts: 145

    Rodney Dangercar
    Member

    Backing up your statement about getting the mount points as close to the spring pads if the bar is mounted with the ends to the frame:

    My OT '78 MII has the rear sway mounted this way (ends mount to the body, center mounts to 8" axle housing). The mount points at the axle are inboard of the leaf pads by just a couple of inches. The sway bar ends mount to links on body brackets that can pivot as the axle moves so that there is no binding. Staggered shocks, all factory. Corners like a mofo and can push it into oversteer if you get sloppy but real fun to play with when set up right.
     
  25. Ned Ludd
    Joined: May 15, 2009
    Posts: 5,742

    Ned Ludd
    Member

    Parallel leaf springs front and rear? That informs roll centre heights.

    Looking only at the front, with stock parallel leaf springs the front roll centre will be at the height of the spring eyes, maybe 8" above the road? If we expect your CG height to be around 20", that means the roll moment arm as regards the front end (it's actually a bit more complex) will be around 12". With ifs, the front roll centre would be more like 2" above the road, and the roll moment arm about 18". So all else equal, the roll moment with ifs will be about 50% more than with parallel leaf springs. On the other hand, with ifs you've got around double the spring base, so perhaps four times the roll stiffness at any given bump stiffness.

    So, unless you can get the roll moment arm down to less than about 4½" (i.e. the roll centre height above about 15½" — viable with a solid axle but not safely with any independent suspension I know of except one) you'll benefit from an anti-roll bar.
     
    JSchmitz67 likes this.
  26. 29Sleeper
    Joined: Oct 25, 2023
    Posts: 1,048

    29Sleeper
    Member
    from SoCal

    Last edited: Aug 27, 2026
    JSchmitz67 likes this.

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.