Ultimate SWB Brake Thread

[304065]

Well, B D has been diligently searching for information about the brakes on the SWB cars. For those of you scoring at home, B D has a 911L and is looking into modern parts that are compatible with the rear discs- the original discs are $360 each.

So I thought it might be good to have all that info in one place, not for purely altruistic reasons, but because I know my '66 is going to need the same one of these days and I want to be ready.

So, here's some data from the factory spec books.

Total effective braking area: 185cm^2
Brake disc diameter, 2000, 2000T: 282 front, 285 rear

911S Vented (for reference) 282.5mm front, 286.0 rear

Parking brake: drum diameter 180mm, lining width 32mm (25mm on LWB), total effective braking area 210cm^2

Value "a" based on disc thickness when new-- this is the dimension from the face of the hat to the inner surface of the rotor- front 35mm +/0.1mm, rear 62 or 62.25mm +/-0.1mm, disc thickess new front 12.7 -0.2mm rear 10.0-0.2mm (10.5-0.2mm for 62.25mm disc) (from 70-on rear "a" is 76mm)

For vented discs, again for comparison, value "a" front 35mm, rear 65mm, both +/- 0.1mm, disc thickness 20.0 -0.2mm when new.

Wear limits- solid discs- minimum disc thickness when evenly worn-- front 11.0mm, rear 8.5mm- for the vented discs, 1.0mm per disc side (18.0mm min thickness)


Part numbers- front disc 901 351 401 11 solid -68
vented = 901 351 041 16
piston 35mm 901 352 099 10

rear disc 901 352 401 10 solid
vented = 901 352 401 15

[304065]

901 352 041 15 = $360.26!

[304065]

From the ATE web site:
Rear 944 discs
PORSCHE 928 352 041 02
PORSCHE 944 352 041 02
Trade Numbers: 420112
Fit. Side Rear Axle
from MY 10/1981 to MY 12/1986
Ø 289,0 mm, Br. Disc Thickness 19,9 mm, Min. thickness 18,7 mm, Brake Disc Type Ventilated, Finish Alloyed / High-carbon, Num. of holes 5

[B D]

Additional info here:
http://d240157.u39.zeonhost.com/forum/showthread.php?t=6377
http://d240157.u39.zeonhost.com/forum/showthread.php?t=6580

[B D]

Brake Caliper Rear 911S/L for vented rotor is a L wide with a 38mm piston
left: 901.352.965.32
right: 901.352.966.32
Rebuild kit: 901.352.998.00 (actually for rear M Caliper)

Front caliper for 911S/L for vented rotor is M caliper with ?mm piston
left: 901.351.965.22
right: 901.351.966.22
Rebuild kit: 901.351.964.11

If spliting the caliper make sure you use the new seals and torque them properly. First 7lbs. (pattern 2,3,1,4) then 17lbs. (pattern 2,3,1,4).

caliper half seals (seal ring): 901.351.928.10

[B D]

Still waiting for the rear 944 rotors, will follow up with machining process.

Thanks John

[mjshira]

anyone contacted verburg?

[B D]

Note be very careful removing drivers side rear soft line. Must use two flare nut wrenches one on the back of connection and one on soft line, unlike the passengers rear side which goes in to a T-connector held in place. Getting a wrench in there is very difficult, its a 12mm.

[B D]

Originally posted by mjshira
anyone contacted verburg?

Bill is the resident expert for brakes but only knows '69 and up. Everyone has been contacted and this is the main source now for SWB brakes.

[mjshira]

cool, good luck. I have not reviewed any threads on this topic so I will be interested to read as info is gathered.

[Hoffman912]

have you guys tried classic and speed parts?

he has a very good brake system he sells. both trade in and out right buy. He sells completely remanufactured brake caliper , drilled and vented rotors, braded lines, etc. EVERYTHING is basically brought back to brand new.

here is somthing Will (the owner of classic and speed parts) recently posted on another board.

It has been brought to my attention that some confusion may exist in regards to our remanufactured brake caliper program. Here is what we offer:

We start with an original, used Ate caliper as a core. Each caliper is completely disassembled (both halves of the calipers are split apart as well), media-blasted and crack-tested and inspected. At this point we lose approx 30% of the incoming cores.

Each caliper is then yellow zinc plated, as Ate did (and still does). The following NEW parts are ALWAYS installed: stainless pistons, new through-bolts and nuts, new bleed valves and dust caps, new seals and new bridge pipes/rubber dampners (where applicable).

We package them in a kit with new, reproduction expander springs, locating pins, springlocks and hardware. We offer an exchange program for convenience, complete with nitrile gloves, zip-lock bags (to prevent drooling), re-useable packaging and a UPS Ground label for the safe return of the core. So far people find it remarkably effortless.

We can offer to do the same treatment to your supplied cores, but it would take 2-3 weeks and if your cores fail the inspection process, you would incur an additional cost. (personally, I can see no reason to do this. If you were to put a brand-new, original replacement Ate caliper on your car, it could look significantly different that what you are replacing.)

Our price for a front kit is $390.00 complete. Our price for the rears (65-68) is $430.00 Rears for 69 are not yet available, I expect them to be approx $390.00 the set as there are no bridge pipes and have only one bleed valve. We charge $100.00 each for cores, refunded upon receipt, whether they pass or fail. We do not package them with pads, due to the many flavors available.

I hope this clears up any confusion about our products. If you have any questions about this or any other product we offer, please contact me or call us directly...we'd love to hear what you have to say.

Sincerely,

William Pringle
CSP-USA
626 445-0108
william@csp-usa.com

also, Will's proiducts are unbelieveable. exceptional quality, nothing spared, and no compromises on any of his parts. he is an honest parts guy, and an all around excellent guy. i cannot say enough about his quality or his service.

here is a pic of the rotors (front) on one 912ers car. the rears are drilled or vented based upon your preference. if you want stock he has those too.



btw, no mods needed. it is a bolt on kit, works with stock calipers

[mjmoran]

The 944 rear just apparently needs 1/16 - 1/8 inch removed from the perimeter of the rotor to fit. This only would work on a wide L caliper from a 67-68 S/L. To add vented rotors to a non vented rear SWB car, one will either have to find a wide L caliper and go with that (the wide Ls were not only wider, they have 38 v 35 mm pistons) or I am currently looking for a fabricated braket to add an M caliper back there. The M caliper has a 3" spacing and the L has a 2 1/4 bolt space. I will keep you posted.

Cheers,

[Hoffman912]

csp's vented rotors work with stock calipers.

[mjmoran]

stock calipers meaning non vented narrow L calipers?? That would be one mighty thin rotor...not sure if I would trust it on the track or street. Also the better bias with the 38mm piston is an advantage.

[B D]

Harry good info but Will does not have a cheap solution for the rear rotors of 911S/L. His brake kits are good for non vented rotor 911 and 912's. He actually advises many 912'ers not to upgrade to S brakes because of the rotor cost.

Michael I was hoping you would share your info on this subject.

[mjmoran]

One other way to "update" the calipers on an early L non S type would be to make them wider. Since the fluid passes thru tubing rather than the bodies of the caliper, a spacer would need to be made like on the wider model and another length of tubing bent. Not a big deal. I would think that you could also have the bore machined out to 38mm...maybe even 42mm as in a Carrera caliper! Have never looked into this. Maybe there is a spare out there that I could mess with to see the viability of this route.

Thinking outloud here...

Cheers,

[Bill Verburg]

Wish I could help, many of you have contacted me privately but in the words of the famous Sgt. Schultz "I know noszing" about the early brakes anyway

[mjmoran]

BD...any info on the 944 rotors yet? I talked to Will Pringle and he did not think that the rotors will fit...just curious.

[B D]

The rotors fit, they need to be slightly reduced in diameter. The part I am having trouble with is finding a machine shop that can reduce the rotors, they are too big for the average auto machine shop. I will have the shop who does the work take some exact measurements of both rotors to share and compare.

Also the parking brake area may be slightly larger I needed to adjust the sprocket to grab the rotors.

[mjmoran]

Great, I just sent you an email BD.