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I have a few questions regarding the assembly of the rear trailing arms.

My chassis is a 69, and I purchased the narrowed rear arms from VMC. I wanted to do a shorter torsions, so they wouldn't stick out past the plate covers, and I purchased the HD Spring plates to complete the assembly.

For some reason my mounting plate on the trailing arms, seems to run inline with the location of the spring plates. If I mount the spring plate on the outside of the trailing arm, it puts the plate at a terrible angle, and makes it difficult to place the torsion cover-and just doesn't seem correct. The trailing arm is installed with both washers towards the outside of the bushings.

What am I missing here? hopefully, everything that I purchased is compatible.

Thank you, for any input!IMG_3355 - CopyIMG_3356 - CopyIMG_3357

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I did irs with short (swingaxle) torsion bars/end caps and found stock rubber bushings worked best.  The aftermarket red plastic bushings needed a lot of work for the end caps to fit properly and every time I put weight on the rear of the car they still squeaked, even when greased.  Stock bushings, lubricated with talcum powder is (I think) the way to go.  Gordon used some type of grease in his car but I found that the rubber just absorbed the grease (yes, Gordon, I used the same type), so went back to the talcum powder (which is, coincidentally, the factory procedure).

For spring plates I ended up taking some stock swingaxle units, cut them down to fit and liked how everything moved way better.  The aftermarket spring plates were just too stiff for good movement.  And if you're looking to fit the widest tire/rim possible, the adjustable plate takes up over ½" of room, and you know there's not much room for rear tires on these cars.  I know guys here say they like the ease of adjustability, but realistically, once most guys set rear ride height they'll never touch them again, SO WHY CARRY ALL THAT EXTRA WEIGHT (or pay for something that when you think about it, you don't really need)?  Doing it via indexing the torsion bars 3 or 4 times is more work, but once it's done, IT'S DONE!  And you're waaay faster at it by the time you're finished.

The 1967 911R style 7" Fuchs with 195/60's just fits with type 1 drums and stock trailing arms.  I took a pair of 15x6" Fuchs to a local wheel specialty shop and they added 1" to the inside.  Not a cheap way to go (Green's Automotive charged $500 for the pair) but it is what it is, I guess. I have some type 3 rear drum assemblies ready to go which will require narrowing the trailing arms.

The modified spring plates are also much lighter-

  • stock double irs spring plate- 2514 g.
  • Swayaway adjustable irs for 21¾" torsion bars- 2598, 2530 g.
  • stock single plate irs- 1779 g.
  • aftermarket irs with short (21¾) bars- 1776 g.
  • stock swing axle, cut down to fit- 996, 997 g. (a little more file work would have made them exactly the same but I was really bored by that point)

As well as having to be shortened, they need about 1/8" cut from both the top and bottom to match stock irs spring plate width (for full suspension movement).  Weight difference- 1602 g (3½ lbs.) PER SIDE!  And that's suspension (sprung?) weight- the only better weight reduction is rotational (wheels, tires and drums/rotors).

lightened spring plate- cut down for irs

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Last edited by ALB
@LI-Rick posted:

Al, that 996 gram weight is with all the holes drilled?

Yes Rick- that's as it sits (it may be before paint).  I look at that pic and think a little more could be taken off the top and bottom, there's room for a few more small holes and you'd get another 30? 40? 50 or maybe even 60 grams, but they're on the car and I'm finished with them.

I believe this is off of an aluminum bodied Spyder re-creation-

lightened spring plate 2

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Last edited by ALB

Some of the 1969 (only) beetle suspensions had dual spring plates in the rear, so they fit on each side of the big forward facing tab on the wheel hub on the diagonal arm.  That is the same rear suspension as on a Porsche 924.  I'm pretty sure that the rear disk brakes are bolt-on (but mega-buck$$$, too).  You can see photos of mine (it has the dual plates per side) in the article I wrote on setting rear ride height, here:

https://www.speedsterowners.co...rear-ride-height--vw

On that version, the rear toe-in is set by moving the hub forward or back or, if really out, with wedges (or thin washers) between the plates and the hub casting to push the hub slightly to get it aligned, which is much harder to do with the dual plates.  The purpose of the dual plates is to prevent any toe in/out flexing in hard cornering.  It works great.

I don't know if this was a standard thing on '69 VW sedans or some sort of factory/dealer option, but there weren't a whole lot of them out there.

Just to throw a wrench in the stock VW bushing love-in...

The stock bushings on my car broke down within 5 years, and created a nice squeak any time time the spring plate moved. I put Saco yellow prothane bushings in it and everything started working better.

I think they've been there for 10+ years.

Also - I'm a fan of reducing unsprung weight as much as the next guy - but there's no way I'm doing anything at all to reduce the strength of the rear suspension in side-loaded situations. Al's pictures scare me, and I'm not usually scared of much. I've got the double wall spring plates. There are times when too much is just right.

Last edited by Stan Galat
@ALB posted:

I did irs with short (swingaxle) torsion bars/end caps and found stock rubber bushings worked best.  The aftermarket red plastic bushings needed a lot of work for the end caps to fit properly and every time I put weight on the rear of the car they still squeaked, even when greased.  Stock bushings, lubricated with talcum powder is (I think) the way to go.  Gordon used some type of grease in his car but I found that the rubber just absorbed the grease (yes, Gordon, I used the same type), so went back to the talcum powder (which is, coincidentally, the factory procedure).

For spring plates I ended up taking some stock swingaxle units, cut them down to fit and liked how everything moved way better.  The aftermarket spring plates were just too stiff for good movement.  And if you're looking to fit the widest tire/rim possible, the adjustable plate takes up over ½" of room, and you know there's not much room for rear tires on these cars.  I know guys here say they like the ease of adjustability, but realistically, once most guys set rear ride height they'll never touch them again, SO WHY CARRY ALL THAT EXTRA WEIGHT (or pay for something that when you think about it, you don't really need)?  Doing it via indexing the torsion bars 3 or 4 times is more work, but once it's done, IT'S DONE!  And you're waaay faster at it by the time you're finished.

The 1967 911R style 7" Fuchs with 195/60's just fits with type 1 drums and stock trailing arms.  I took a pair of 15x6" Fuchs to a local wheel specialty shop and they added 1" to the inside.  Not a cheap way to go (Green's Automotive charged $500 for the pair) but it is what it is, I guess. I have some type 3 rear drum assemblies ready to go which will require narrowing the trailing arms.

The modified spring plates are also much lighter-

  • stock double irs spring plate- 2514 g.
  • Swayaway adjustable irs for 21¾" torsion bars- 2598, 2530 g.
  • stock single plate irs- 1779 g.
  • aftermarket irs with short (21¾) bars- 1776 g.
  • stock swing axle, cut down to fit- 996, 997 g. (a little more file work would have made them exactly the same but I was really bored by that point)

As well as having to be shortened, they need about 1/8" cut from both the top and bottom to match stock irs spring plate width (for full suspension movement).  Weight difference- 1602 g (3½ lbs.) PER SIDE!  And that's suspension (sprung?) weight- the only better weight reduction is rotational (wheels, tires and drums/rotors).

lightened spring plate- cut down for irs

Did you say Baby powder?



When Will that baby be finished

Last edited by IaM-Ray

I have a '69 pan under Bridget the Midget and it's got the dual spring plates. I believe it was a one year only thing. Is it possible that the way it's made is ever so slightly different from all other year VWs, such that the trailing arms won't properly swap and therefore the modded, narrowed ones won't either?

Asking for myself...as I'm going to be getting under that car in the near future and was thinking a set of narrowed arms might be just the ticket.

@edsnova posted:

I have a '69 pan under Bridget the Midget and it's got the dual spring plates. I believe it was a one year only thing. Is it possible that the way it's made is ever so slightly different from all other year VWs, such that the trailing arms won't properly swap and therefore the modded, narrowed ones won't either?

Asking for myself...as I'm going to be getting under that car in the near future and was thinking a set of narrowed arms might be just the ticket.

I believe the trailing arms are the same, Ed

Me, too.

And you know…….    Those dual spring plates per side in a 1969 VW?   While they certainly weigh more, they work with the triangulated diagonal arm to keep the rear wheels so true and corner so much better that I don’t begrudge the added weight.  It’s the same set up used on both the 924 and 944.  It’s like having a stealth 924 under your VW Sedan!  (Without the bigger engine).

Me, too.

And you know…….    Those dual spring plates per side in a 1969 VW?   While they certainly weigh more, they work with the triangulated diagonal arm to keep the rear wheels so true and corner so much better that I don’t begrudge the added weight.  It’s the same set up used on both the 924 and 944.  It’s like having a stealth 924 under your VW Sedan!  (Without the bigger engine).

I believe this to be true as well. Of all the places to save weight, I'm not inclined to do it here.

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