So I was looking at simple ways of improving the braking system on my car and read the PP article on the 320i front caliper upgrade. Then I search the forum and found many threads on the subject. I also really appreciated Eric Shea's comments on the bias and the proportionning valve (or anti-lockup valve).

Let me describe my setup: stock 2.0, Fuchs, sway bars, 100lbs rears, 195/65. Spirited daily driven.

In vue of my reading I have 3 topics/questions on this:

1- Isn't there a rear caliper available that could be used in the back that would be proportional to the front 320i yet keeping the hand brake?

2- Why would someone want to switch to 19mm MC in the stock setup? Yes you will get a quicker response but you will also need to press even harder on the pedal.
I can understand it if you replace the calipers to larger chamber volume.

3- Per Eric's suggestions, I could simply make sure that all my calipers work properly, adjust the gap on the rears, and invest in good pads. But then which of the suggested ones more specifically:

Porterfields R4-S: AP30 or AP31?
Hawk: HB172F or RHB172F?
KFP Magnum: KFP-30 or KFP-31?

Thank you,

1) no simple rear caliper is available
2) it helps with overall feel, but thats an opinion and you could be absolutely fine without the upgrade
3) I'm a big fan of the porterfields street compound on street cars... (I prefer KFP on light weight race cars)

I had the same questions before I started my simi-restoration. I went with Eric's suggestion to replace the existing stuff and add the 19mm MC. I can't tell you the results yet as I don't have the engine back. Eric supplied AP 30 R4-S and AP 31T R4-S Porterfield pads.

Biggest improvement I made was rebuilding the calipers and replacing the soft lines. They may look ok, but if they are stock, they are bad. Pmb has them, and ones that actually fit.

All, Thanks for the info:

Brant:
1) Makes sens
2) I will probably keep my stock one since it is fairly new (3 years)
3) Porterfield

ww914:
I will give a call to Eric Shea to discuss this

Underthetire:
I forgot to mention that I already have SS braided lines in the front. Is it needed in the back too?

Don't know about Ss lines, I use rubber, but yes, they should be changed.

dont skimp on something that will keep you
and others safe.....and prevent further cost down the road .....JMO
MikeC

All things being equal, the one thing we should always make sure is 100% perfect is the brakes in our cars. Doing all of the work and spending all of the money we do on these cars to have a brake failure and possibly injure someone or wreak our cars, is just not worth it. When it comes to brakes please do not try to cut corners. BTW, I am not trying to infer that the OP is doing that-

Brakes fully restored to stock condition are just fantastic and will stop you in any situation. If your 914 is not a 150 hp race car with slick tires there is no need to "upgrade".

I agree that the stock system in working order is just fine.

However, I never understood why more HP should result in bigger brakes - as long as the car is street driven.

SPEED....TAKES MORE BRAKES TO STOP WHEN YOU CAN REALLY HAUL ASS...STOCK 914 DONT HAUL ASS

MikeC

Yes, 914/6 rears, but they may be cost prohibitive for CSOBs

Your best bet unless you plan to go deep, both into the project and your wallet, is to make the stock stuff the 'Best it can Be'

FWIW...I've run the 320i fronts with stock rears for 10+ years and love them, I know it goes against what others say, but for street its great...when you go past that in terms of performance--i.e. doing Auto-X you will REALLY notice the bias being off as it will feel like the rear of the car wants to come around on you. I've probably adjusted my driving style to compensate for it over the years.

All that being said, I have all the parts to swap over to my 'big brake' set up where I've got 911 vented disks all around, Aluminum Brembo's for the fronts and 914/6 GT rears...it took a lot of time and $ to get there and I still can't seem to actually find the time to get it all on my car...

I think it might be that no one has looked for one for a while...

Most rear calipers always used M10 bolts... but there is some newer stuff which is now using M12 like the Mk5 Golf.

There is an alternative rear caliper. Ferrari 308. That's Italian for "shitload of money".

The Cap'n

M10? Are you talking about mounting bolts?

I've done a number of 911 handbrake conversions and a number of 914-6 caliper applications. It always ends up 6 to 1 or 1/2 dozen the other.

Brant is correct... well sorta; there "is" a simple solution but it simply costs money. 914-6 calipers. They have the same 38mm piston a 911 rear caliper would have and they use the same pads a 911 used all the way through 1983. This is simple because it simply bolts right up and uses 914 handbrake cables etc.

There are a ton of threads on 911 handbrake conversions where you will need to grind the bearing housing, fit a 911 handbrake (early preferably) and find a cable solution. I've tried almost all of those too and in the end when you add up calipers, handbrake assemblies, oddball cable solutions etc. you're pretty damn close to the cost of a pair of rare 914-6 calipers. The problem is, most 914-6 caliper go for around the price most have paid for their 914 so... back to Brant's statement -- There's no simple solution.

I have aluminum bodied 914-6 rear calipers in the works. Who's in?

Or - Maybe try these?

If they don't require a second mortgage on the house and they are more available then the Ferrari 308 you have my attention. Please tell us more

David

The chances of finding a set of 914/6 rears or Guccis' (Ferrari 308) for less than the National Debt is chancy (specially when Shea is involved )

I have never examined the /4 casting that well ... whether it could be bored out to 38 mm I don't know.

I've seen posts here where people put a brace on the master cyl to keep the metal from bending when you really push on the pedal. It's simply a piece of metal with 2 big hose clamps holding it to the MC, and bracing against the steering rack (Ithink).

Search or someone will chime in with the link.

CFR makes a nice MC brace.

Those are Alfa Milano rears. 38mm pistons, AP31 911 pad size... Ohhhhhhhhh... bleeders on top, too bad. I'm sure someone could perform a workaround.



You could but then you'd be left with:
1. No dust boot.
2. Same small pads
3. A bill for even more money wasted trying to do stupid $hit.

Or you can wait for our 914-6 Aluminum Rears...

Do tell more

If they're loaded and under 1K I'm all over it. Just get them done by the end of February. After that my wife finds ways of spending all of my bonus check.

NEW 914 parts rock

Thank you all for the input.
The purpose was to look at cheap alternatives (hense BMW front) but I see there is no such thing.
I will verify the adjusment on the rear since they are probably due and maybe replace pads to see if it makes a difference. And for those who are concerned, I wouldn't drive with faulty brakes. I easily locked both front weels at 60mph this morning.
The braking on the car is fine, but it doesn't compare to my 330ci, nor that it's supposed to, they are 40 years apart and completely different beasts.
As for your new aluminum rears Eric, I'm sure it will be a nice product, but probably not in my price range.

Bottom Line: BMW's are a perceived "upgrade" by many. They will give you a better bite in the front but they will throw off the braking dynamics. That said, there are worse places to be biased heavy in a mid-engine car (like the rear... which tends to cause a spin if the steering wheel is anything but centered when you go to use your brakes).

So... get your system up to snuff and get some great pads. You can rebuild the calipers yourself or, we can do it for you. Happy to help wither way. We have all the kits and seals needed and the right pads.

As mentioned by someone else in this thread... a 914 brake system in great working order is nothing to thumb your nose at. It will stop your car and stop it well. It's a system designed for you car too... keep that in mind. It's funny you bring up the later car as I believe this is one of the first areas of displeasure people come to with 914 brakes. My Cayenne can stop on a dime with my toe on the pedal. Car's from the 70's are a tad different. If you can lock up your front wheels then the calipers have done their job; in the 914 or the 330ci. No amount of money, time or caliper will stop you faster if your tire isn't moving.

Good luck. Let me know if I can help.

QUOTE: You can rebuild the calipers yourself or, we can do it for you.

"We" Eric, what do you have a mouse in your pocket?

A little Irish rub there buddy!

Jeff

Actually... Two Eric's. Eric Munoz is the master...

Sorry, but I'm calling the here.

Just because your 0-60mph is faster it doesn't mean you need "bigger" brakes.

are there any methods of checking the condition of a current 17mm MC? we've just replaced all the lines and rebuilt all 4 calipers, the only thing left is the MC, it looks old? rusty? replacing it on a whim is difficult due to my budget.

As others have said, dont skimp on brake components. If you think you have an issue, replace.

Sorry! I can't help myself. It's....


6 of one or half dozen of the other

Or

6 in one hand or half dozen in the other

Mangled expressions are a peeve of mine!

Wheres the hard on smiley?

Coming soon but it's a "tough road to hoe" (for Bill)

Oh no...another one! You like torturing me! As someone who chopped weeds out of rows of tobacco plants on my uncle's farm when I was 10, 11, and 12, I can tell you that it is, indeed, a "tough row to hoe"!