73 Porsche 911 E/S brake calipers

[quickstep]

My future project car is a 73 E Targa with Comfort package as well as stabilizers and Koni's
When reading about the history of these cars I noticed that a lot of people upgrade the brakes/calipers to S specifications.

Looking at the front and rear brake calipers it seems to me the front ones were restored sometime, while the rear ones don't.

Can someone confirm if the front brake calipers are orginal and are these E or S specs?

Thanks,


Guido

[ThomasTe]

Yes, those are correct aluminium calipers for your 1973 911E. E and S front calipers are the same. They are usually just called S-calipers. They are made of aluminium and the distance between the bolt holes are 3.5". Your koni struts will have date marks to tell you what year they are, too.

It looks like the calipers just need a good clean-up, new compensating lines, new repair-kits, new pistons, pads. The mounting hardware could either be replaced or re-cromated. Make sure you remove the knock-back mechanisms from the back of each old piston and fit them to the new pistons. New pistons don´t come with these things.

Here a nice pic of the different aluminium calipers:

[Richardnew]

That is one great image. Very very helpful. Thanks.

Richard Newton
Some Tech Ideas

[chris_seven]

These calipers were not only standard on the S and E but were fitted to the 911T when a Sportomatic Transmission was specified.

The ATE Seal kits are missing a large diameter O Ring that seals the access plate which is held on by the Allen Screws.

If you source new O rings I would try to find them made from EPDM - NBR and Viton aren't so good.

52mm ID x 3mm Cross Setion

I have a bagful if you get stuck.

[quickstep]

Thanks for this help. Somewhat confusing to find out what kind of caliper exactly have been installed by previous owner.
Can you upload a similar picture (comparison) of rear brake calipers?

Thanking you in advance.

[Jim Breazeale]

Thanks for this help. Somewhat confusing to find out what kind of caliper exactly have been installed by previous owner.
Can you upload a similar picture (comparison) of rear brake calipers?

Thanking you in advance.

The rear calipers are steel and rarely changed.

Regards

Jim
PS: Don't be misled by the color of this caliper. I just ran it in my bead blaster to knock off 40 years of crud. They should have a yellowish cast to them, originally

[quickstep]

Under what condition or circumstance were S-calipers installed on a E car.
I have a E car with S-package (470 comfort) but does this apply also to the brakes?

Is there a good reason to go for S-calipers instead of the 'usual' T calipers that were instaled on T and E cars?

Thanks.

[Flieger]

hydropneumatic struts (the ones that did not use torsion bars) and/or sportomatic gearbox.

hydropneumatic struts only had the 3.5" spacing and they didn't want to make new ones with 3" spacing. sportomatic did not allow compression braking (engine braking) so more friction brakes were necessary.

By the way, I believe "S" was the designation from ATE, not Porsche. Stood for schwer (spelling?) meaning heavy. M was presumably medium and L leicht. This was not the weight of the caliper (S calipers were lighter being aluminum monoblock) but the weight of the intended car application or duty cycle.

[fgmec]

Under what condition or circumstance were S-calipers installed on a E car.

Always installed.

[damsroy]

My understanding is that S calipers were installed on S and E cars up to 72.
In 73 E cars had the non S calipers installed with the 3" strut spacing.

Always installed.