40mm drums on 30mm backing plates

[eurodub]

Hello
I have a 1960 bug, September (1961 model)

After bodywork and paint, it cam down to the running gear.

In the back, I went for the 40mm drums with 40mm shoes. all new.

I am trying my best but I cannot simply make it work. The shoes and everything there seem to push too much out and into the new drums, locking the drum before I can even tighten the castle nut.

is there a 40mm rear backing plate for 5x205 setup?

How is the conversion possible? I am out of options here...



Thank you
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1960 1200 model 117 deluxe ragtop
1974 T2 Westfalia Campmobile
1976 MK1 Golf

[Bub]

You need the correct bearing 'cap' and spacer setup. That's what creates the proper clearance for the various brake shoe widths.
keep in mind it's ALL a package deal when getting brakes to work properly.
17mm vs 19mm master cylinder, wheel cylinders too.
Just increasing the friction surface on the shoe means less force per area for the same brake pedal pressure.
I'll admit *most of the time* it works out fine and you'd hardly know the difference, but if it ends up having weak or odd braking it can come down to mixed up parts.
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[eurodub]

Thank you!
I will try to source everything from a late beetle.
I did have/still have issues with the gearbox oil coming out from the small o-ring.. so maybe your assertion is right.
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1960 1200 model 117 deluxe ragtop
1974 T2 Westfalia Campmobile
1976 MK1 Golf

[EVfun]

You need the later backing plates, wheel cylinders, adjusters, and brake hardware kit. That will let you assemble late model 40mm wide rear brakes on your early Bug but you will run into another problem. You are going to need drums that will fit. The original ‘58-‘64 drums with the smooth hub center (like the front drums) are too narrow for the wider shoes.

Late 4 lug drums have the needed inside width but the splines are too long. They can be made to work if you have a machine shop shorten the snout (I think by 15mm). You can get a set of ‘65-‘67 rear drums (6mm wider) and then have a shop turn them slightly to maximize braking surface. They have the available space to fit 40mm brakes shoes with help.
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[esde]

Yes, just been through this,68 and later backing plates, with 65-67 drums with slight modifications, or thing drums. I think you can also use type 3 rear stuff, but it is hard to find and $$$.

[eurodub]

I will add pictures later today.
on the left side I was able to put everything back, only have the issue with leaking small O-ring. I guess I can add some spacer on the central part that squeeze the O-ring and test.

The sad part is that new drums are already oval from new! never thought I'd see that, but this is the only way of having the wheel turn ok, then lock up a bit, then loose again, repeat.

The drums are the later type 40mm, but with 40mm. they have that " flower" in the middle.

a desperate measure would be to scavenge the rear drums from my 58 ragtop and use all with 30mm shoes. but, I wanted new drums, that is why I purchased them...
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1960 1200 model 117 deluxe ragtop
1974 T2 Westfalia Campmobile
1976 MK1 Golf

[esde]

[Bub]

[EVfun]

Think about the loaded brake backing plate all by itself. If the backing plate was made for 40mm wide shoes the centerline of the bore the brake adjusters fit into is 20mm out from the shoe resting stops on the backing plate. If the backing plate was made for 30mm wide shoes the centerline of that bore will be 15mm out from the shoe resting stops. So, 40mm wide rear brake shoes require 1968 and newer rear backing plates.
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[runamoc]

[eurodub]

Well, this is why I still love this forum.
Lots of valuable info that doesn't get lost like on fb and other social media crap.

the backing plates I have are clearly early 30mm type.
I would guess the adjusters are 5mm to the inside than on 40mm backing plates.

I will try to source some later backing plates and test.

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1960 1200 model 117 deluxe ragtop
1974 T2 Westfalia Campmobile
1976 MK1 Golf

[modok]

None of those parts match.
Those backing plates only have two SPOTS for the shoes to rest against, thus need the slave cylinder and abutment screws to have narrow grooves to hold the shoes in place.

If you use WIDE grooves then you need the backing plates to have the 6 pads for the edges of the shoes to rest against.

OR

If using that slave cylinder ON that backing palate it would be necessary to weld up the edges of the brake shoes and make them wider so they properly center in the wider grooves.

[EVfun]

[AlteWagen]

[runamoc]

[AlteWagen]

[runamoc]

[esde]

[AlteWagen]

[runamoc]