Brake Upgrade in progress need input.

[goat]

I am getting ready to redo the brakes in my car.
At this time I don't have the money to convert to 5 lug for bigger calipers. So I will be working with what I have. This is my plan.
First upgrade the 17mm master with a 19mm.
Slotted/ drilled rotors front and rear.
Replace the front and rear calipers. any opinions on ate verses Cardone?
Stainless steel brakes lines, and new agressive brake pads.
This car is going to be autocrossed by my wife this year and driven on back roads.
any help would be great.
Thanks Tim.

[racer]

Stock rotors (which are not vented), solid, imho are best. Drilling removes materials. Slotted might be ok, but seriously, a 914 doesn't need to brake alot.

x2 on master cylinder upgrade

What kind of pads? I ran porterfield R4(?) on my latest 2.0 and they were nice.

What kind of tires will you be running?

[goat]

thanks.
I am running Dunlop sport tire not the most aggressive but will have to do till they wear out.
Not too sure on pads. have like pagid in the past.
going to pull the calipers off. I know the left front has a little seizing going on, Pulling to the left, but not too sure how bad.

[URY914]

Just buy new rotors and bearings. Don't drill them.

[eric523]

another vote for porterfield pads. I use the r4S on my track car and they work well with no noise. stock rotors, stainless lines, bigger master, SRF

[campbellcj]

+1 I had exactly the same setup on my 73 2.0 although I think I used the regular R4 pads which did squeal sometimes. I never had heat issues on the local tracks here or in autocross.

[Dave at Pelican Parts]

ATE is the caliper manufacturer; Cardone is a rebuilder. An inexpensive one, from what I can tell. Eric Shea is a better choice, IMHO.

Aggressive pads are cool; the Porterfields have a good rep.

Slotted rotors may do better in the wet.

All the other stuff IMHO is unnecessary. The stock brakes, when in good working order, are more than capable enough for anything but serious abuse. And autoX is very much not that.

--DD

[goat]

Thanks for the input.
Will try the porterfields. I think I will try to rebuild before buying a new set.
I have noticed that when driving and applying the brakes then touching the calipers after stopping the left front will be cool and the right very warm. Not sure what is going on but after pulling it apart I will have a better idea.

solid rotors sound like the best way to go, and cheaper than the drilled too.

yur914.. Good call on the bearings no idea how old they are probably original.

[eric523]

Going to need seals for the bearings too, don't forget those on your parts order.

[goat]

Originally Posted by eric523

Going to need seals for the bearings too, don't forget those on your parts order.

Will order those too. who knows what condition they are in...

[goat]

Thanks Dave for the Eric shea pmb performance. checking into their brake restoration.

[kachemakian]

Hi Tim,
We just had the discussion on the Jag forum that I belong to about going to a "different than stock" master cylinder diameter. When I bought a new master cylinder for my 914 the opinion that I got here on this forum was that: if you do not mind a very stiff pedal, the 19mm is ok, otherwise stick with the 17mm even though it costs more to get a replacement. I just ran the numbers and the 19mm would take 125% as much pedal pressure as the 17mm to apply the same pressure to the calipers while only moving 80% of the distance in pedal travel. This would be fine for a man with a strong leg, but since a lady would also be driving my car, I opted for the 17mm. My car is not going on the race track, so maybe someone else can share their opinion about whether or not the 17mm master cylinder could cause you to run out of having "enough pedal" on the track.

Leon Smith
72 914 w/Rayco kit

[rfuerst911sc]

Your caliper sticking might be caused by the rubber brake line hoses collapsing internally. If doing a brake job and if these are old they are cheap to replace. There is nothing wrong with a good working Porsche brake system.

[goat]

Leon.
interesting data on the 19 verses the 17 master cylinder. I have no reason to believe that what I have is bad at this time so I think I am going to leave it alone at this time. Even if it means more brake fluid and replacement later.
I am getting new brake lines for sure. The lines I have no idea how old they are....

[Rob Kalis]

All,

I totally agree with keeping the 17mm MC. I completley rebuilt my system, including rebuilding all 4 calipers, 4 new rotors, new pads, SS brake lines. The system works very well, afterall, German enginnering went into it. Unless you plan to use larger calipers, you do not need a larger MC. The 17mm MC is sized for the stock calipers. If you enlarge the MC without the calipers, your braking performance for a given peddle pressure is immediately worse by 25%, like Leon said. Why give up the mechanical advantage that is designed into the system (press harder for the same amount of braking). People think that because the 19mm MC is used on the 911, that is automatically better. Not true in this case.
Have Fun dude
Rob Kalis, Mechanical engineer
1975 914 w/2270 torquer

[kachemakian]

Hey Rob, it did make me wonder why everywhere that you read about it, at Pelican, on Ebay, yatta, yatta, they always call going to a 19mm master cylinder an upgrade??? I can see where if you changed out everything to a Porsche engineered 911 system, that would be an upgrade. A lot of thought and testing went into matching master cylinder diameters to the calipers they are installed with at the factory. It seems to me to that the "bigger is better" mindset has prevailed on this issue. Maybe Dave could get the verbage changed here in the Pelican parts listing. It states that "you should upgrade to the more powerful 19mm master cylinder ". What do you think?
Leon
72 914 Rayco Slantnose Boxster
76 V-12 Jag w/14 brake caliper pistons

[goat]

Reading over the facts involving the 17 verses the 19 master cylinder makes alot of sense.
Very good stats on the differences.
Maybe a better phrase might be "The 19 is better for car with larger brake calipers".

[infraredcalvin]

Porsches will forever be known for thier braking systems, although the more I cruise on these boards i notice that no matter which forum you frequent there is a portion of the population wishing for more braking. My first few cars were american muscle of the 60's era - drum brakes (no power). I was used to very hard pedal pressure and very little braking. When I got my 914 the pedal travel was what bothered me the most. I rebuilt my calipers, did the ss lines, 19mm mc, more agressive pades, and used super blue brake fluid. Once all was in great working order, i found that the biggest improvement to braking was with the proper pads and a careful bleeding of the system (inclusive of the proportioning valve). I kept the 19 mm mc I only because I prefer a stiffer pedal with less travel.

These brakes work great as long as they are maintained properly, I think we just get spoiled with disks all around, and very little weight to stop.

[trekkor]

My well maintained stock system with Porterfields handles my most aggressive track sessions.


KT