Brake upgrade for early 912.

[Merv]

Awesome! Thanks for that. So essentially, all I really need is the callipers, pads, SC disks, tailored brake lines and it'll all bolt on?

As with me. I had to remove the spacers in the calipers as I was using the SWB solid rotors. No leaks and stunning braking.

[Fishcop]

Be careful to ensure your brakes are balanced. I would not upgrade the fronts in isolation - do you homework on whether the solid rear discs are compatible with ventilated fronts. It's probably not an issue, but there could be bias. For a little extra, get PMB's rear S spacer kit. Buy 944 rear discs and I can give you the machining specs.

[Duck4cover]

Be careful to ensure your brakes are balanced. I would not upgrade the fronts in isolation - do you homework on whether the solid rear discs are compatible with ventilated fronts. It's probably not an issue, but there could be bias. For a little extra, get PMB's rear S spacer kit. Buy 944 rear discs and I can give you the machining specs.

Thanks John, I bought the Brembo brakes. Does anyone know where I can get a seal kit for them? I've sent you a PM re info above. Will the rear callipers suffice and mate up OK with 944 rear disks and PMB's rear S spacer kit or will i need to run a different set up on the rear? Also, will a new but standard brake master cylinder be OK?

Thanks and sorry in advance for all the noob questions! Appreciate everyones contribution.

[Fishcop]

Hi David

I sent you a PM

Here's a link to my SWB car that has photos which may be helpful... http://typ901.org/showthread.php?t=5462&highlight=race

[Fishcop]

You can see the spacers in the 68S calipers in the lower portion of this photo. And now that I think of it, you may need slightly longer cross-over pipes.

[Merv]

David I got the seals, new bleeders and so on from PMB. Alfa spares may have same in Australia.

[Duck4cover]

Hi all, I've rebuilt the calipers, fitted braided hoses, new disks all round, new pads all round, a new standard sized brake master cylinder but after driving, it still feels like it takes a long time to pull up even with my foot to the floor. Any idea what this could be?

[Fishcop]

Without being rude Duckman, have you had much time driving cars without power/vacuum brakes?

I know for me when I first drove a beetle after learning to drive in a corolla, un-powered brakes were very strange and 'wooden' to me initially.

One other question relates to the new MC - what size? Should be 19mm but ATE made an identical unit for Mercedes in 21mm and swapping these over means extra pressure is required on the pedal.

[Duck4cover]

Without being rude Duckman, have you had much time driving cars without power/vacuum brakes?

I know for me when I first drove a beetle after learning to drive in a corolla, un-powered brakes were very strange and 'wooden' to me initially.

One other question relates to the new MC - what size? Should be 19mm but ATE made an identical unit for Mercedes in 21mm and swapping these over means extra pressure is required on the pedal.

Without like sounding like too much of a noob, this is my first Porsche and also my first pre '70s car and although not the first non power assisted brakes it still feels like it takes a little longer than it should despite pumping them, maybe the calipers, pads and disks need to set in?

Yes, it is the 19mm. Thanks to everyone for the responses! Appreciate the insight.

[Fishcop]

Definitely give the brakes some time to bed in and for the pads to burn off surface impurities. Discs need to be take up to temperature several times on a quiet road with some hard and prolonged braking. Get them smelling funky to be sure.

Another thing that can upset braking is poor wheel alignment and suspension set up - are you feeling the front of the car compress and 'dive' under load without feeling flighty? If so, then it's really just a matter of finding a nice bit of road to have a play on and get a feel for it all. Easier said than done in an urban environment though.

Lastly, if a 911/912 is your first foray - the dynamics are distinctly different having the engine at the rear, it just feels really different when you load the stop pedal.

[PCM911T]

The brakes will get better once you have used them a few times and the pads bed in. Find a deserted road and jump on them a few times to get the piston rubbers moving( they can hold the pistons back) and warm up the pads. Also check that you have bled the hydraulic system of all air, especially the rears, elevate the rear of the car for a while to bring any air to the bleed nipples, then move forward.
Cheers
Paul M

[Merv]

Go through the proper break in process. They should be firm and very effective. My early Brembos are superb and compare to our modern cars. If you have a spongy pedal or slack in the pedal, then you will need to set the pads correctly with only a small gap to the disc. Do you have pads set? No air bubbles coming out still? Did you start bleeding with the most remote wheel?