S-brake calapers, Differance between Options

[BarberDave]

(IMG:http://www.914world.com/bbs2/html/emoticons/smilie_pokal.gif)
What is the difference between the stock front brake calapers and what is refered to as the S-Calpers. Thanks Dave (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

[ClayPerrine]

911 M and A calipers a cast iron. The M caliper has a 3" bolt spacing. The A caliper has a 3.5" bolt spacing. The S-caliper is an Aluminum caliper with a 3.5" bolt spacing.

I have a pair of S calipers for sale if you want a pair.

[michel richard]

Clay,

You forgot another important difference:

S calipers brake better than stock calipers.

P.S. By the way, this is a fact that was proven true, by the seat of the pants method, on one tired old 914. It is not the result of scientific analysis of a statistically significant sample using double-blind testing methods. As a result, YMMV.

P.P.S. This qualifier may molify Curt Curtis and his rant in another post (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)

Michel Richard
914 2.2E six MFI

[Eric_Shea]

(IMG:http://www.914world.com/bbs2/html/emoticons/agree.gif) with bod-a-dem-der-guys.

(and I can't feel them flex...)

[Dave_Darling]

The stock calipers are relatively small, and made of steel. They have a 3" (center-to-center) mounting bolt spacing, and are sized to go over solid (non-ventilated) rotors on the stock 914 struts.

S calipers are from a 911; they were optional from about 1969 through 1977 or so, and standard up through ~1979. They are made of aluminum but are larger than stock 914-4 calipers. I don't think they're any lighter than the stock -4 parts, but I am not sure. They use a 3.5" (c2c) mounting bolt spacing, and are sized to go over the ventilated front 911 rotors. Those rotors will only fit on 911 front struts, unless you use some fairly trick parts (hey Mueller--are those billet hubs ready yet??). There are reports of S calipers flexing under load, which makes the brake pedal feel more spongey and reduces the effectiveness of the brakes. Others report no obvious flexing. The difference may be in how old and worn the calipers are. ...Or perhaps not...

Brand-new S calipers are still available, I think. They're absolutely stupid money, though--over two grand apiece. Used ones are much, much cheaper. Especially when purchased as part of a complete 911 front end.

--DD

[Eric_Shea]

Here's a sheet I put together for my 911RS project. Shows only about 2lbs.:

Weight Savings
911 RS Project

Original Equipment Factory Weight Revised Weight Savings
Steel Hood 35 10 25
Front Bumper 23 6 17
Rear Bumper 25 6 19
Engine Lid 12 6 6
Seats 31 15 16
Upholstery 56 6 50
Radio 1 0 1
Roll Bar 0 35 -35
Calipers 14 12 2
Totals 197 96 101

Original Weight 2244
New Weight 2143
Original HP (125hp) Ratio 18.0 lbs. per hp
New HP (240hp) Ratio 8.9 lbs. per hp