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I'm setting up the rear ride height on my VW based Speedster replica. (1972 Swing Axle BJ)

I want it to ride a little lower than stock (does everyone use standard Beetle ride height for their speedsters?..) I have dropped the front a little with spindles.

I don't have the body on or the engine on but I want to set it up correctly now so I don't have to try and do this job later with the body on when things will be tricky to access.

I would like to see photos of people's cars, the level of the arch compared to the wheel and the rear torsion settings used... This would help me a lot. Any advice would be appreciated if you have done this yourself. Chris

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If the rear suspension is at stock height now, you can take one outer spline pre-load out and you will lower it 1-1 1/4". Taking 2 splines pre-load out (and just popping the spring plates back on) will lower the rear 2-2 1/2" (or a little more) and this is low enough that you'll have to be watchful if the engine has a deep sump. It will all depend on how good the roads are in your area. With a swing axle, as you go lower you not only introduce negative camber (and abnormal tire wear) but you put more angle on the spade ends of the axles and this will cause more wear to the spade ends, spacers and side gears in the differential. As well, now the axle bearings at the outer ends aren't getting lubricated as they should. For the most part this is a relative non-issue if the car sees mostly city streets (with a lot of turning and suspension movement), but if you like to do big highway miles (where the rear suspension is operating at it's lowest point continually for hours on end) you may want to re-think it. 

2 things- most guys have found that much more than stock front shocks ride unnecessarily rough (the front ends in these cars are really light) and the red poly steering coupler is crap; toss it now before it tears at speed and injures or kills you.

Hope this helps. Al

Yup, Beam adjusters (I prefer the Avis version) on the front beam are spiffy for doing that final fine-tuning, regardless of normal or drop spindles.

I wrote the article below a while back and it is up under the "Resources/Knowledge Base" tab at the top of this page.  That version has photos, but here is the text for you, with the very handy table for setting ride height.  It shows you how to adjust up or down in 1/4" increments.  

Remember, that it is fruitless to try to set ride height on just the pan - you really need the car completed, engine in and all that jazz, to get it set up right.  Otherwise, you'll just be in there re-setting it after the car is complete because it won't be where you want it.  Also, the balance, left to right, is set by varying the height of the left or right rear as the car sits, so, again, you'll need the car completed to do that.  Resetting ride height on an assembled car isn't all that difficult, and it can be done in less than an afternoon.  Here's the article (I hope the formatting carries over from my service manual).  The process is identical for swing-arm or IRS cars.

One last thought:  You CAN go the route of adjustable spring plates on the rear to do any adjusting, but you may still have to adjust the plates on the torsion bars to get into a preferred range for the adjustable plates to give you what you want.  I don't have adjustable plates since I just set my normal plates up to where I wanted - And I haven't touched them for over ten years now.

3.2.8  Setting Rear Ride Height

Detailed instructions here (you may need to be a Supporting Member to see them and the photos):

 Adjusting rear ride height on a Speedster Replica

 This article should give you enough information for you to re-set the rear ride height on a VW pan-based Speedster, regardless of whether it starts out high or low and regardless whether it is an IRS or swing-arm suspension (although we’ll be showing IRS suspension in this article).  The job is relatively simple (and what isn’t simple on a pan-based car?) and should take about two to three hours to re-set BOTH sides.

 Make sure that your car has settled the suspension by either driving it around or rolling it back and forth across a 20 foot distance a couple of times.  Start out by measuring the distance from the ground to the top of the wheel well arch on both sides and write them both down. When I started on mine, the passenger side was sitting at 23-7/8”, while the driver side was a mere 23-1/4”  A difference of about 1/2”!

 Once you have the starting heights, you’ll need to decide how you’ll adjust it.  In my case, the passenger side will be left alone and I’ll raise the driver side the needed 1/2”

 We’ll start by getting the car up on Jack Stands such that it is comfortable to work on and securely stable.  Once that is done, remove the wheel on the side(s) you’ll be working on for access to the suspension, and then remove the shock absorber and put it aside. 

 The rear hub is attached to the spring plate by four bolts.  Before you touch any of them, use a metal scribe to outline the hub casting where it attaches to the spring plate, and make a line mark on both the hub casting and the spring plate to reference later on for alignment.  I used a cold chisel a while back and marked both permanently (look close to see the mark).  On my car I have a rear sway bar attached, so the hub mount for that must be removed along with the spring plate bolts, as shown (just swing the bar down out of the way once it’s been let go on both ends).

 Once the alignment mark is made, go ahead and remove all four bolts.  Be careful in case your hub is loose between the spring plates, but it usually stays put.  Now loosen the four bolts holding the torsion bar end cover in place - back them out 1/2” or so to allow the cover to move out.   Place a floor jack under the bottom end of the spring plate(s) (use a wooden block between jack and plates) and slowly jack it up until the inside plate just clears the stop on the torsion bar mount, then use a small pry bar to gently coax it outward and then slowly lower the jack to allow the spring plate to swing down beyond the plate stop.  Remove the torsion bar cover.

 Find a socket that will just fit through the big hole in the torsion bar mount so that it’ll prevent the spring plate from moving up in the next step.  Use a socket extension as a handle and hold it in place while you do the next step:

 Put a floor jack under the brake drum (use a wooden block between jack and drum) and jack it up until it  clears the spring plate - it should be free of the plates.

 Scribe a line along the top edge of the spring plate onto the torsion bar mount as a reference of your start point.

 Now for a little info on how the rear suspension is adjusted:  Rear torsion bar inner and outer splines are different. Inner splines move 9 degrees per spline, while outer splines move 8 degrees, 10 minutes per spline.   Measuring my car (a 1969 Beetle pan with IRS) gives 17 inches between the centerlines of the torsion bar and the axle, so using C = pi(D) you get a circumference circle of 106.814 inches (imagine drawing a big circle with the torsion bar center at the middle and the axle centerline at the circumference). Break that up into degrees and its .297 inch per degree and .005 inch per minute.

 Applying the math gives one inner spline (9 degrees) for 2.673 inches of axle travel (either up or down), and for one OUTER spline (8 degrees, 10 minutes) you get 2.426 inches of travel (either up or down).   Using combinations of inner and outer splines allows a little less than 1/4" travel at a time by going one way with an inner, and the other way with an outer.

 Here’s a table I did to save you all that math:

 Table 1:

U = UP

D = Down

 Inner  -  - -  -  -  -  -  -   Outer -  -  - -  -  -Result (inches)

1D .  2.673 .  . .  .  .   1U 2.426 .  .  . .  .  .  D  .244

2D  .  5.346 .  .  .  .  . 2U 4.852 .  .  . .  .  .  D  .488

3D  .  8.019 .  .  . .  . 3U  7.278 . .  .  . .  . D  .741

4D  .  10.692 .  .  .  .  4U  9,704  .  .  . .  . .D  .976

5D  .  13.365 .  .  . .  5U  12.130 .  .  . .  . .D  1.235

6D  .  16.038 .  .  . .  6U  14.556 .  .  . .  . .D  1.482

7D  .  18.711 .  .  .  . 7U  16.982  . .  .  .  . .D  1.729

8D  .  21.384 .  .  . .  8U  19.408 .  .  . .  . .D  1.981

9D  .  24.057 .  .  . .  9U  21.834 .  .  . .  . .D  2.223

10D  . 26.730  . .  .  . 10U 24.260  .  . .  .  .D 2.470

11D  . 29.403  . .  .  . 11U 26.686  .  . .  .  .D 2.717 

12D  . 32.076  . .  .  . 12U 29.112  .  . .  .  .D 2.964

13D  . 34.749  . .  .  . 13U 31.538  .  . .  .  .D 3.211

14D  . 37.422  . .  .  .  14U 33.964  . .  .  .  .D  3.458

 Ok, so in my case I have to move the car UP 1/2”, so the spring plates must move DOWN 1/2” at the rear axle.  Pretty simple, but I will also be sitting on the driver’s side, so I’m going to increase ride height a little more than that for my weight - say, 3/4” or so.  Looking at the table, I need to go three splines DOWN on the Inner end, and three splines UP on the Outer end.

 Now for the trickiest part of the job, because you want to do each end of the torsion bar separately, but not screw up one end while adjusting the other.  Let’s start on the inner splines first:  Grasp the spring plates and the torsion bar end cap and apply a sideways pressure to them by using the spring plate as a lever so as to keep the outer end from coming loose on the torsion bar.  Now rock/jiggle the torsion bar out of the inner splines but do it gently so you can feel when it just lets go.  Now gently press it back in to feel the splines and move it in the desired direction - in my case I have to move the inner splines 3 up, so I gently start to move the spring plates up, feeling each spline until I get to three, then I push the torsion bar back in as far as it will go.

 Now for the outer splines:  Again, grasp the spring plates and bar end cap and gently wriggle it around to work the end cap off of the end of the torsion bar.  When you feel it let go, gently hold it in place and rotate it in the desired direction - in my case, I now need to go three splines down so I rotate while gently pressing on the cap and spring plates to feel one, two, three splines down and then push the end cap onto the splines, but not yet all the way on.

 For the next step, you’ll need a small container of Baby powder with which to “lubricate” the torsion bar bushings.  The inner bushing is held captive by detents in the housing, so all you’ll need to dust is the inside of the bushing and/or the outside of the end cap where it inserts into the torsion bar tube bushing.  Be liberal - dust it up nicely white, then push the end cap all the way on/in. For the outer bushing, grasp it and slide it outward on the end cap tube, then liberally dust the tube and slide it back into place, then dust the outside of the outer bushing as well as the inside of the end plate.  You can then slide the end plate onto the end cap.

 If you’re not using new spring plate bushings at this time, then the end plate should slide on far enough that it’s bolts will thread into the torsion bar end mount.  If they do not reach, you may need to go get four new bolts the same size and thread pitch and about 3/4”-1” longer to get everything started.  Simply thread the new bolts through the end cover and into the casting and tighten them so that the cover goes on far enough to, one by one, replace the longer bolts with the proper ones.  Get them threaded in, but do not yet tighten them down.

 Re-position the wheel hub flange between the spring plates and gently slide it down more-or-less into place.  You may need to use a small pry bar to get it in between the spring plates again, but it should fall right in.

 We have to get the spring plates back up onto the bottom stop of the torsion bar mount.  To do that, place a wooden block onto your floor jack and position under the rear end of the spring plate and jack it up until the bottom of the plate just clears the stop on the mount.  Now, tighten the four bolts of the end cap cover a little at a time in a cross pattern to keep it even until all four are tight.  Torque them to 30-35 ft. lbs.  Remove the jack.

 Line up the wheel hub holes with the slots in the spring plates, insert the four bolts but do not yet tighten them.  Line up the scribe marks you made earlier and tighten the single bolt at ten o’clock, then tighten the other three bolts (unless you have a sway bar mount - for that you’ll need to assemble the mount and THEN tighten the bolts.)

Last edited by Gordon Nichols

"I want it to ride a little lower than stock (does everyone use standard Beetle ride height for their speedsters?..) I have dropped the front a little with spindles.

No one driving a Speedster on here is riding at "normal" VW ride height.  I would suspect that we're all two to 2-1/2" lower than that, and some are a tad higher than others.  If the front sits about where you like it with the drop spindles, then just make the rear match the front height and don't bother with front adjusters.  Your steering geometry is simpler with drop spindles, too.

I don't have the body on or the engine on but I want to set it up correctly now so I don't have to try and do this job later with the body on when things will be tricky to access.

You'll be resetting it anyway if you try to set the ride height now, rather than after it is complete.  Setting ride height should be one of the last things you do before getting out on the road.

I would like to see photos of people's cars, the level of the arch compared to the wheel and the rear torsion settings used... This would help me a lot.

Be careful with this - different body manufacturers have different shaped wheel wells. For instance, Robert, just above, has a Vintage Classic-sided car.  His rear wheel well arches are somewhat flat at the top of the arch.  I have a CMC wide-body which has somewhat rounder wheel arches, like this:

IMG_2741

Ride height is limited by the tire size and body style you're running.  Go too low with larger tires and you might hit the top of the tires on the inside of the body if you compress in a dip, or especially on bumps while cornering (ask me how I know this!)  It is a trial-and-readjust process til you're happy with the compromises.

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Replace "ride height" with "corner weight" and you'll all be on to something. The way to do it is with scales, of course, but setting even a production car with actual body tolerances can be a fool's game. Then we go to replicas which are wishfully the same left and right, sometimes off by an inch or more. See where I'm going with this? 

A 911 factory tolerance on fender "height" is +/- 1/4". Say the left is 1/4" high, and the right is 1/4" low. You've now set your car 1/2" differently left and right. If you use weight on each wheel, with scales, your car will HANDLE the same whether turning left or right, bumps, whatever. Can't do that with a tape measure.

Gordon is ABSOLUTELY correct about setting it up when the car's finished, and not before.

The way to do it, like I said above, is with scales, and the driver in the driver's seat. Car should be configured as it is when driving most often. I use a half to 3/4 tank of gas, and all tools and spares.

Good luck.

calmotion posted:

@ALB they are 7 and 8. 205 and 225 x50 x16. The rear left rubs during  left turn and both rubs during deep humps  

Was thinking 215 x50 might help. The left wheel stuck out more and had to do a little negative camber

Was also thinking of raising it a little to see how that works. All four has side has 20 mm wheel adaptor/ spacer

I think 7" in the rear would fix that. I had the same issue rear left and had to raise it a notch. Then I swapped to drilled rotor for the rear.

calmotion posted:

@Bill Prout the 7 “ was discuss. The 8 is nice since it sits nice. Will try to raise it a bit to see if that helps. 

How much room is between the inner tire and spring plate? Since you're running wheel adapters, have you considered getting the rear drums drilled and eliminating the adapters? Is your car swingaxle or irs?

If swing, do you know if it has early or late axle/tube assemblies? If it has late axles and tubes, converting to early (1961-'66) will bring the wheels/tires inboard about 1 3/4" (per side); you could got to either type 3 rear drums or discs for better braking (if the car has discs on the front they won't lock up nearly so quickly) and still be over 1" in from where you are now.

If your car is irs- the trailing arms can be narrowed up to 1 3/8" (would require shorter axles) and even with type 3 drums or discs (both add about 5/8" width per side) the wheels/tires would still sit in 7/8". 

Last edited by ALB

One heck of a lot less work than what I was proposing- I hope it does the trick! Al

PS- Are we going to call you Calmotion for forever more or will you be enlightening us with your first name? You may have noticed that a lot of us are on a first name basis here (even if it isn't part of our screen name).

Last edited by ALB

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