‘74 with ‘84 Carrera brake upgrade

[acme911]

Thanks to the forum experts, I went with the ‘84 Carrera 24MM rotors (vs 20mm) and the matching calipers up front. These also fit within a Fuchs 15” wheel. I also picked up a set of 993 air deflectors and SS brake lines. For the back I went with a new set of stock "M's". Along with new rear rotors, pads and SS brake lines.

The car is mainly driven on the road and occasional DE/AX.

I wanted to share pic’s of the size difference of the front caliper parts. There are many threads on brake recommendations and I just wanted others to see what the forum experts are talking about. As for stopping, the transformation is significant and well worth it. Remember part of the overall equation is in the suspension setup and weight of the car. Our earlier cars even without a weight diet are a lot lighter than an ‘84.(*I have lightened mine).
Bottom line is you don’t have to spend a ton.




Werk in progress

[pdtweeks]

Well done Acme.
I have the same setup on my lightened 3.6 powered ‘83 SC, for same usage as yours....brakes are awesome....confidence-inspiring in the mountain twisties.

[Bill Verburg]

These aren't both front pads, the a and wide are the same pads(except that later pads are designed to accommodate the pad wear sensors)

The upper pad appears to be an M, usually used in back and the lower pad appears to be an A or wide A

[acme911]

Originally Posted by Bill Verburg

These aren't both front pads, the a and wide are the same pads(except that later pads are designed to accommodate the pad wear sensors)

The upper pad appears to be an M, usually used in back and the lower pad appears to be an A or wide A

Bill, you are right. I loaded the wrong image from my phone. At any rate the brakes work great. And thank you for your expertise and help.

[75 911s]

Brake newb here. So you can upgrade to the Carrera calipers without changing the manual brakes to a power assist setup then. I guess the only thing a power assist is make it easier to press the brake down?

[Bill Verburg]

Originally Posted by 75 911s

Brake newb here. So you can upgrade to the Carrera calipers without changing the manual brakes to a power assist setup then. I guess the only thing a power assist is make it easier to press the brake down?

As long as you have 3.5" struts then yes, you can change to the 3.2 Carrera front calipers and rotor w/o affecting anything other than the thermal capacity. Leave the rears alone.

[75 911s]

Thanks Bill. What's your take on the Brembo AM setup?

Photo courtesy PMB performance

[acme911]

Originally Posted by 75 911s

Brake newb here. So you can upgrade to the Carrera calipers without changing the manual brakes to a power assist setup then. I guess the only thing a power assist is make it easier to press the brake down?

Original master can be left in. Also must have 3.5” spacing on front caliper mount. The brake upgrade was done while doing a suspension upgrade.
Hopefully Bill will fill in the details for you.
Here is link to thread discussion about MC’s:

Master Cylinder Question

[juanbenae]

ive done this now to both of my cars. the 1st a spec racer I did extensive cooling with ducting, backing plates directing the ducted air and block offs at the hubs. I was never in need of better brakes even in a #2400 with me on board car. ive since done it on my 74S by selling my late S calipers and with the proceeds was able to get a used set of the larger 24mm calipers, rotors, & rebuild kits and still came out ahead in the "mod" both times I maintained the rear M's and assisted MC on the SC racecar and an unassisted 74 MC with no ill effects in either case.

I will often suggest this mod to guys wanting to "upgrade" to 964, 944t or other brake options that in order to do right per Bill's input seem very costly and complicated for minimal returns compared to the Carrera set up. I guess that the Carrera set up does not have the larger mono block look or the cool PORSCHE logo embossed on them for all to see and notice their brake upgrade. KISS= keep it simple stupid...

[7783911]

why the switch to SS Braided lines...had you experienced mushiness?

[acme911]

40+ year old lines. Due for a change.

[gtc]

Since your '74 doesn't have pad wear sensors, you can use SC pads in those '84 front calipers. They cost a bit less and don't have the sensor cut-out.