Caliper Spacers

seafeye · 07-22-2017, 02:25 PM

Got a nice set of S aluminum calipers for the front of my '71 911. They fit the 3 1/2" spacing for the mounting bolts.
My old steel calipers used spacers too offset the rotor. I think they were 4mm.
Is there a part number for the ones for the S calipers?
I think they should be 2.5mm. Does this sound about right?

bkreigsr · 07-23-2017, 06:56 AM

Do a dry-run test mounting to see if the 'S' calipers are centered over the rotor - you might not need them.
Nothing wrong with stacking a couple of M14 washers to compensate, instead of the factory spacers.
Bill K

seafeye · 07-23-2017, 07:16 AM

Ok. I put a couple washers I had that were about 2.7mm. Still a bit offset. Wondering how much is acceptable.

bkreigsr · 07-23-2017, 07:44 AM

Still looks too tight for me.
Curious, did you compensate for removing the dust shield?
Bill K

seafeye · 07-23-2017, 08:18 AM

Ahhhhh

No. It never had one on there. How much space does it take?
These were the rotors that was on my car to begin with.

bkreigsr · 07-23-2017, 09:15 AM

The three 13mms bolts each used a M13 lock washer. If you don't use them, and the shield, the rotor will end up that much closer to the caliper mount ears, and you may not get the proper left/right symmetry. I used two M13 flat washers (each) in place of the shield/bolt/washers that I removed.
Perhaps splitting hairs, but I got the clearance I needed.
Hopefully, one of the experts will chime in to present a more learned solution.
Bill K

Trackrash · Trackrash's Garage

What year and type of struts are those? How thick are those rotors?

I recently put '73 Koni struts on my '71 and installed "S" calipers with no spacers. Calipers seem to be centered, no unusual pad wear or weird braking.

I'll try to get a picture, if you want.

seafeye · 07-23-2017, 11:13 AM

Just looking at the brake shield picture. I don't see how it would affect the distance of the caliper. It uses the three smaller bolts. Because it slips over the spindle, does the thickness of the plate affect how far seated the rotor and hub?

seafeye · 07-23-2017, 11:27 AM

I just took it all apart again. Here is what I have:
1971 911E. No idea if the struts are original. They are bilstein but painted Koni orange.
Rotors are 20.40mm think.

Trackrash · Trackrash's Garage

Is the bottom ball joint attachment a pinch bolt or a wedge bolt?

seafeye · 07-23-2017, 12:40 PM

I'm going to go with pinch bolt. It looks like a regular bolt.

djpateman · 01:07 PM

Does this strut not require the seal ring? #24

Trackrash · Trackrash's Garage

So there is a slot in the bottom of the strut that allows it to be clamped to the ball joint?

I have not seen one with a nut on a bolt to do that. I also did not know that there were Bilstein struts available in '71. Does it have Bilstein stamped on the strut? If so there could also be a year stamped. My guess is it is a newer strut, SC?

Maybe one of the experts has done this before and can offer a better response. FWIW, my rear calipers have washers as spacers, so it should be no problem using them to center your calipers.

You may want to make absolutely sure that your wheel bearings are fully seated.

seafeye · 07-23-2017, 01:24 PM

What year is that diagram for with the sealing ring?

seafeye · 07-23-2017, 01:34 PM

I found this spacer on Pelican

djpateman · 07-23-2017, 02:18 PM

I thought that they all used it. There is also the O-ring behind it; #23.
The bearing seal rides on this ring, and the O-ring is the seal on the spindle.

seafeye · 07-23-2017, 04:01 PM

Well looks like I need the spacer and O-ring. Thanks guys will keep you posted.

Trackrash · Trackrash's Garage

That is a newer strut. Up to '71 the strut was split and had a clamping bolt to clamp it to the ball joint. Like in my photoshop. Also the older struts had a flair so the upper half was a larger diameter than below the spindle.

Someone has modified your strut. It should have a wedge bolt. See #20 in post #12.

seafeye · 07-24-2017, 08:08 PM

Ok thanks I see what is happening here.
I ordered the ball joints for a '71. Now does it make a difference if I use the bolt vs a wedge bolt?
Cause if I have to use the wedge I'm going to need the different ball joints. And of course order the different parts for a later strut.

Trackrash · Trackrash's Garage

Since your strut has been modified to use that bolt you have, it may be that it was intended to work with the older ('71) style ball joint. It looks to me like the hole was drilled too large for a wedge bolt to still work. But hard to tell from the picture.

I think you will have to see which ball joint will work. And make SURE it is tightly clamped. I'd use a lock nut AND locktite with the bolt you have, if it was me. If that bolt gets loose and comes out it won't be pretty.

As far as the insert goes, it looks to me like you have a Boge strut from an SC. But I'm not an expert and there were a number of changes through the years on how the inserts were attached.

There is usually a stamp on the strut tube as to the manufacturer and a date. If you show a pic of the top of the strut and the nut that holds the insert in, someone here may be able to identify it.