Category: Rear Suspension

Questions we’ve been asked about rear suspension- parallel vs. triangulated, leaf springs, air ride, etc.

Dear Welder Series… why are there three holes on the axle brackets?

Dear Welder Series…

Hey DW
Hope all is well sir and you are having a good year so far.
A question came up in our shop this weekend and I am wondering if you could let me know the correct answer when time permits please!

The axle brackets on your parallel 4 link kits- the 3 holes on the rear for shock mounts- are the 3 holes used for initial ride height setup ONLY, or are they options to be used for future ride hide adjustments??

Great debate here on whether they are meant to be used adjusting the ride height whenever you want or if they are meant to be a ‘one time’ use during the chassis build.

Could you let me know the official response please? (I have a $100 wager on this)

Regards,
John

Dear John…

Hi, John.

DW suggested we give you the answer you want for a cut of the action… (Just kidding…)

My “official” answer is: Nobody loses this bet.

Usually the 3 holes are used as a lower mounting point for coil-overs or ShockWaves. They can be used as shock mounts when conventional air bags are used, but my first thought is for coil-over suspension. That’s the basis for my answer.

Coil-overs and ShockWaves have a “designed ride height”. https://welderseries.com/tech/tech-sharing/coil-over-mounting-offset/. We feel a custom vehicle should be built with the suspension at ride height. https://www.welderseries.com/Right-Height-Vehicle-Set-Up-Tool-p83035424. Physical constraints might dictate the (ideal) location for the upper coil-over mount. The 3 axle bracket holes will give some flexibility to the upper mounting hole location, since the (fixed) coil-over ride height is important to the vehicle ride height. So the wager winner is the initial ride height setup only… maybe…

The 3 holes allow for future adjustments that might involve different coil-overs, different wheel/tire combinations, or a different “look” desired for display at a car show. I have moved the lower coil-over up a hole when going on a vacation trip with a “kitchen sink” in the trunk. So the wager winner winner is the adjustable person… maybe…

I hope you two have a laugh over this and save your money for Welder Series parts.

Thanks for writing. It’s been fun answering.
Paul Horton

Dear Welder Series…

Thank you very much Mr. Horton

As always I appreciate your responses. (I will selectively edit parts of your response and attempt to cut you guys in as I might lose now)

Another question if I may- wouldn’t adjusting up or down a hole as you suggested at the bottom throw off your driveline angles? Or would the difference be minimal?

What brought this about is a wager on my Model A coupe- it rides a touch too high in the back & the wager was whether you can drop it a hole and not throw everything off. 

Thanks, John.

Dear John…
Raising or lowering the rear by 1” on a Model A will change the driveline angle by less than 1/2 of 1 degree. I’d consider this minimal and should not cause a problem… unless the driveline angle is already borderline. Lowering the rear could be offset by shimming the transmission mount.

Dear Welder Series…

Well sir I appreciate your insight very much regardless of the $100 I just lost haha

Thank you very much regardless

John.

Dear Welder Series… how much hp?

Dear Welder Series…
How much hp does your universal 4 link kit support? And can you estimate shipping to Saskatoon SK.

Dear Jesse…
A lot depends on the tires you are running and how you plan to beat on things. We build parts for street rods and feel they are top quality. A parallel rear 4-link kit does not give the same traction advantage that a race-type, non-parallel 4-link does. Freight from our door to yours is 10% of the order with a minimum charge of $15 and a maximum charge of $60.

Dear Welder Series… Panhard bar adjuster question

Dear Welder Series…
Received my order today. Your parts are absolutely fabulous. Just as advertised.
I do have a question though. Take a look at the pictures. The threaded bolt that goes into the threaded end of the pan hard bar on the end that gets welded to a bushing has a slight angle cut in it. Different from the others. I was wondering if it was supposed to be welded on an angle for mounting purposes or just a flaw in the cut off the bolt.

Dear Mike…
Hi Mike, thanks for your comments. The adjuster included in the universal panhard kit goes on the red end bracket and is notched on a 5 degree angle to clear the pinion. You’ll also notice the two frame tabs are different lengths – this is to compensate for the angle of the bar at the frame.
Thanks again!
DW Horton

Dear Welder Series… coil over specs?

Dear Welder Series…
I just purchased a 1950 Chevy 3100 truck where the seller installed WS21906 in the front and WS318500 in the rear of the original frame. I was hoping you could suggested an affordable set of coil overs that would work with this setup. Unfortunately I have no idea as to what I should be looking for in terms of the stroke, lengths, dampening, etc.. Thank you.

Yuchol

Dear Yuchol…
Congratulations on your new project! These are great looking trucks.

I suggest blocking the truck at ride height to establish coil-over ride height.

If the upper mounts for the front shocks have been installed, the ride height for the coil-overs will be the center-to-center distance between the mounting holes on the lower arms and the brackets. If the frame plates have not been installed, click here for the manual…pages 2 and 13 will help.

If the rear crossmember has been installed to mount the top of the coil-overs, the truck’s ride height you have chosen with the mock-up will give you the coil-over ride height. If there isn’t yet a place to mount the top of the coil-over, please consider the crossmember

 

The coil-over mounting angle is discussed here. The coil-over ride height can be determined when you mock up the crossmember and mounting points.

Regarding the coil-over stroke, generally longer is better as it will offer more suspension travel. Other factors or interference points also come into play. Viking, RideTech and other North American companies make quality coil-overs.

I hope this helps with your decisions.
Paul Horton

Dear Welder Series…
Thank you so much!

Yuchol

Dear Welder Series… thru frame tie rod end mount on the rear?

Dear Welder Series…
I have a question concerning your thru frame hair pin mounts. Have you ever seen them used on rear radius rods with a single front mount?

Dear Steve…
Hi, Steve.  I haven’t seen them used in that type of rear suspension.  But I believe our through-frame mount would be stronger than any other tie rod end mount.  The amount of support for the tapered stud, from the large area of the tapered stud to the button head is 2”, so actually wider than for any tapered hole bracket.

I hope this answers your question, but please expand on it if I missed your point.

Thanks for looking at Welder Series parts.
Paul Horton

Dear Welder Series… Sway Bar Install – 32 Ford

Dear Welder Series…
Attached are pictures of my plan for the Welder Series rear sway bar kit that I am installing on my ’32 Ford project. At this time it is tacked in place and I think it will work as I hope. I still need to tweak the positioning. I ran the bar through the square tube crossmember and the arms ended up directly over the rear axle. Also you can see the Welder Series exhaust hangers near the transmission tail housing and one behind the pipe passing over the rear axle. These are the parts that I recently ordered from you.

Dear Welder Series… four link frame brackets on the outside?

Dear Welder Series… 
We are a local community college automotive collision repair program, we are building a 1968 C10, and would like to install a rear four link suspension. But we are looking to install it on the outside of the frame rails, to make room a fuel tank. Could you help?

Octavio

Dear Octavio…
Octavio, I just now left a message on your voicemail but want to confirm by email.

The rear 4-link can be installed outside the frame rails if you have 4″ clearance between the frame and the tire. One thing to be aware of is that the frame will likely have to be notched for coil-over clearance if the coil-overs are to be mounted at an angle.

We offer a 10% discount to schools using our parts in their projects.

Thanks for looking at Welder Series parts.

Paul Horton

Dear Welder Series… ’56 Chevy air ride four link?

Dear Welder Series…
Hi Paul, i have a 56 chevy wagon and know for a fact that because the location of the fuel tank the only way i can place a 4 link in the car is putting the bags in front of the axle. Can i modify this kit to do it and work properly?

Thanks, Gon.

Dear Gon…
The bags will work ahead or behind the axle, but it might be tricky modifying the standard air bag 4-link kit to do this.

Our Rear Four Link Package Kit could be used and the axle bracket could mount the shocks instead of coil-overs. We could produce an air bag bracket that would come off the front of the axle tube, tangent to the top of the tube. This still leaves an issue with Panhard clearance, but you could consider a diagonal locater from the front lower bar bracket to the opposite axle bracket.

I hope these thoughts prime your imagination. Thanks for looking at Welder Series parts.
Paul Horton

Dear Welder Series… which master cylinder?

Dear Welder Series…
Good morning!

I was just wondering if you had a suggested master cylinder to use with your universal under floor brake kit?  Is there one from a specific vehicle that I can pick up from the local parts store?  I have also attached a couple pictures for you of some of your products on my build so far!

Cheers,
Jon

[Jon used some custom length bars on his parallel four link, and our #229000 thru-frame tie rod end mount.]

Dear Jon…
Jon, nice work on your frame! Looks like you have nice facilities, too!

Any GM or Ford master cylinder will fit our brackets, thanks to the slightly elongated mounting holes. Corvette master cylinders are low profile so work nicely in many street rod projects. Be sure to check the street rod shops for them. We found more bore sizes were available and the price was good.

Thanks for the pictures! (And for using our parts.)

Paul Horton

Dear Welder Series… X Frame Four Link?

Dear Welder Series…
Hello,

I know your product is universal but am wondering if you know of, or have experience with using this on an “X-Frame” car. I have a 1957 Cadillac which is an “X-frame” that I’m considering using your kit on. I thought I might as well ask to see if you have any info. Thanks!

Dear Alex…
Thanks for asking, Alex. I don’t have any experience with the x-frame Cadillacs, but from the pictures on the internet, it looks like a big job. The rear 4-link installation sheets, for the parallel and triangulated kits, are on our webstore below the description of the kits.

http://www.welderseries.com/Rear-Four-Link-Kit-Parallel-p51428446
http://www.welderseries.com/Triangulated-Four-Link-Kit-p49926314

Using them, you might be able to see where the frame mounts could be put and what interference points there will be.

Sorry I can’t give a more specific answer, but thanks for considering Welder Series parts for your project.
Paul Horton

Dear Welder Series… four link for towing?

Dear Welder Series…
Can these be used on a crew cab dually that will be doing some towing up to 10,000 lbs? Also is the hole cut big enough to fit over a 14 bolt which I believe is larger than most street axle tubes??

Dear Corey…
Corey, we make parts for street rods/hot rods and I feel our kits are overbuilt. But I don’t know where their limit is. I might try this if it was my own project, but I won’t suggest you do our R&D. The axle brackets are built for a 3″ diameter tube. They can be opened up for the larger Ford tubes.

Thanks for looking at Welder Series parts.
Paul

Dear Welder Series – triangulated upper bar location

Dear Welder Series…
I am researching the install of your Triangulated Four Link on a 57 Pontiac. Do the rear mounts of the upper bars need to be on top of the axle tube? I noticed, even in the pictures of some installs on this site, that some rear upper bar mounts are on the FRONT of the axle tube. Is there a problem mounting them in front of the tube. I am not sure, in my case, I have the room to mount them on top without cutting up the floor.

Your input would be greatly appreciated.

Dear Writer…
Putting the upper bars on top of the axle tubes gives better leverage advantage than on the front of the tube. The bars can also be longer than with the front mounting position. A downside is that the bar will mount 2 – 3″ higher than with the front-of tube position and this can cause floor interference.

Dear Welder Series… triangulated four bar bar lengths?

Dear Welder Series…
How can you calculate the length of the upper and lower bars so to know that your rear four link will work effectively ? I have a 1956 chevy bel air will use coilovers!

Dear Ken…
Ken, a triangulated rear 4-link is fairly forgiving if you need to change bar dimensions a bit. Our standard bar lengths will work well in your Chev.

Thanks for looking at Welder Series parts.

Paul Horton