Ultimate SWB Brake Thread

[beamonk]

you can reduce the size of the rotors with a regular brake lathe. The old machines are easier, but a new one can be used with a little creativity. Volvo has a four puck caliper that either fits a non vented rotor or a vented rotor. One may have to cut the rotor some to fit, but they work well, ATE's i believe. The skinny caliper is on a 75 190 ?and the vented is for a later car. 3" spacing. The calipers can be sourced really cheap $40-60. They fit under 14" wheels on my Datsun Roadster.

[mjmoran]

John,

This Volvo caliper will fit an early SWB rear? They have a 2 1/4 spaced bolt pattern. If your talking 3" spacing, there are plenty in the Porsche bin to choose from...and therefore there are a nice assortment of performance pads to choose from.

[dsfnctn]

I wanted to help with the brake upgrade but am sorry to say that I am trying to get this sailboat ready to race to Hawaii in july and it has kept me from playing with the cars. I will tell you that for my SWB carsI bought the complete front and rear suspension from an SC and the front was a direct bolt on and for the rear I went to my machinist ,built a spacer did a little grinding to the caliper and at the time I wasnt concerned with the hand brake, but I swapped the backing plate from the newer bannana arm and the narrower shoes and it all fit back together . I used the newer brake line setup with bigger master cylinder. [img]]

[dsfnctn]

Last fall at Portland with 2.7 Gamroth RS spec. motor

[beamonk]

no, I was speaking of the fronts, just posting an alternative

[mjmoran]

dsfnctn, thanks for sharing. That is definetely the way to go! SO, the e brake from a later system fit? That would certainly fix all the issues we are dealing with...Do you have e brake?

Good luck on the Sailing, and talk with you when you return.

Cheers,

[dsfnctn]

I dont know how it all worked out but it fits fine and the E brake works perfect. I am in the fabrication bussiness and would be willing to document the modification and duplicate the spacer if there was some interest. At this time the rear suspension is off the car because I am working on the Bannana arms to help the alignment because the car is so low and the boat is in my way. Right now the keel that I put on two years ago seems to be loose so I have to pull it and still leave for LA next week. Pic attached

[Fleming]

Yes the 1983-86 944 rear rotor can be modified to fit the vented rears on the 1967 911S. The outside dimension is machined to 285mm. The mechanist used the brake drum lathe and reversed the cutting head to do the outside (as opposed to doing the inside of a drum brake). It leaves just a tad of the wear indicators on the outside edge.

The two retaining screw holes need to be repositioned on the 944 rotors to match those on the stub axle of the 67. We rapped brass shim stock around the studs, slid the new over the existing rotor to center them together and drilled the holes. Counter sinking the holes to match the metric screws was the hardest part. We ended up roughing them in using a wood screw counter sink bit that was shaped to the correct bevel - but being just two winged it chattered and needed to be finished with a modified die grinding stone bit.

Now it's on to mock-up brake cooling ducts to get air into the 1/2 inch wide opening to the center of the rotor. Should have something in the next few weeks.

Clam shell coolers worked very good on the 65's non-vented rotor, but may be self defeating on the outward forced center cooling of the 67's vented rotors. They are outward vaned aren't they?

Bob
300 149
306 956S

[ttweed]

Originally posted by Fleming
Yes the 1983-86 944 rear rotor can be modified to fit the vented rears on the 1967 911S. The outside dimension is machined to 285mm....The two retaining screw holes need to be repositioned on the 944 rotors.

So that's it, Bob? The E-brake hat is the correct size and everything fits perfectly there?

Thx,
TT

[Fleming]

TT, The first measurements when the parts came in were the same, so it went out to the mashinist.

The trial bolt-up looked good. I'm still fitting other suspension parts and fab'ing cooling parts and have yet to rebuild the calipers, so it will be a while till it's on the ground and operational. I'll keep you posted.

Bob

[blau911]

Guys,
I have a 67 911 with stock (i.e. non -vented rear brakes). I was playing with the idea of upgrading to vented discs in the rear, but after reading baout the cost and hassle of upgrading to the early 911S rotors/caliper set-up, I am wondering if there is a vented rotor with the same width/diameter available that I could simply buy without requiring me to change my rear caliper set-up?
If not, I have an email address for a guy in Germany who manufactures rotors to whatever spec you want to order. He advised that he could manufacture basically any size - as long as the order was big enough to make the cost reasonable. To get an idea of cost, I would need to provide exact spec's and he could give me a price. Anyone else interested in pursuing this if there are no cheaper off-the-shelf alternatives?

[B D]

The rotors you want are available see Harry Hoffman's post earlier in this thread. The 912 set up is the same as the base 911. Or call or email William Pringle
CSP-USA
626 445-0108
www.csp-usa.com
william@csp-usa.com

[mjmoran]

Well guys, I am off on doing the same as dsfnctn has done to the rear of the SWB car. Have the trailing arms off, Carrera brake backing plates, rotors, and calipers ready and pulling the hubs tonight. I will keep a photo documentation on the process. Seems, so far, the major pain is going to remove the hub and have to replace the wheelbearings the rest looks straight forward. Since I already have added a complete 930 front suspention and Carrera brakes up front, I need more in the rear...this should do it. disfntn, I emailed you a while back on the spacers...I hate to reinvent what has already been done, so if you are around and available, let me know what you have.

Cheers,

[mjmoran]

Well, not straight forward by any streach...more to come. Heck, its only money right???

[rvanderpyl]

Bump to find out what has happened here

[mjmoran]

R Vander Pyl,

Thanks for reminding me...I have been VERY busy this Spring and Summer. Soon (with in the month) I will do a write up on the brake change over. With lots of time and manufacturing I have come up with a great upgrade for my 68 -- and have made it much easier for others to do as well with a kit-type version of what I have done. And it should be a nice weekend project for most. In the meantime, here is a link to see what I have done. I can say with track time and a few Auto X's this season, I have been very happy with the brakes versus the early calipers...no fade as of yet and much easier to find parts. They look stock as well unless one REALLY knows what they are looking at...

SWB brake thread on Early S reg.

Cheers,

[rvanderpyl]

Sent you an email, but just to bring this to the top for other interested partys.

[mjmoran]

R Vander Pyl,

I just made a general post on the early S board link. Added you to the interested people as well.

[mjmoran]

[Fleming]

Henry has a listing looking for the 911S rear rotors over on the for sale list - so Ill post over here also.

67S Rear Disc's

Here are a set of regular 944 rear's (1983-1986) that has been brought into 1967 911S spec's.

The outside is machined (on a truck brake drum lathe) to 285mm.
Add the two set screw holes in the appropriate locations.

The critical spec of "a" is correct at 65mm. (The wore out S disc measured 64mm?)

The inside dimension for the emergency brake shoes is at the correct 180mm.

The differences are:
the hub face hole is at 102 vs. 90mm - but this does not matter cus to doesn't ride on anything.

That hat surface is 6mm vs. 9mm. You get 3mm longer stud contact surface.

The vain openings are inset from the rear edge but the EB shoe still has full contact.

With the wheel mounted you can't see any of those items.

The weight is 11.5 lbs for the wore out and 12 lbs for the fresh disc. With a thinner face and a larger hole I would have thought it would be lighter - so there is more material in the disk surface for heat sink.

The machine cost of $50 and a pair of disc's at $80 each was a good option for this car.

Bob