I have been thinking about doing the beemer front disk brake upgrade. The only thing that bothers me is the loss of the parking /(cough, cough) emergency brake. I had an idea to look for a motorcycle front disk brake rotor mounted to the axleshaft with a cable operated brake assembly mounted to the tranny (I think there are three useable bolts on the RH side). Anyone play with this idea before?

You have a parking brake on your front wheels???

This is the mod that you use calipers from a BMW 320i on the front location and move your front calipers to the rear axle. The article is here http://www.pelicanparts.com/techarticles/9...MW_calipers.htm

Just because you CAN do something, doesn't always mean you SHOULD. I think you'll find little, if any, improvement over stock brakes redone right. When all is said and done, the rotors are the limiting factor. Oh, and cost.

Yet another instance of the term "upgrade" being flung about with little or no regard for its meaning.

The Cap'n

Personally, I think it's the tires that are the limiting factor.

The extra brake caliper as handbrake/e-brake has been talked about a lot, and even done once or twice I think. There was talk of using a mechanical (cable-actuated, no hydraulics) go-kart caliper bolted to the trans, and a rotor sandwiched between the inboard CV and the output flange. I don't know if that actually happened.

There was also talk of some other cable-actuated caliper out on the trailing arm, clamping the regular rotor. Obviously not in the same place as the regular caliper; I think the thought was to have it on the trailing side of the rotor?

But the best brake upgrades are to make sure your stock system is in good working order, with fresh fluid, and that you have decent tires.

--DD

OK, on a scale of 1 to 5 the improvement would be 1-2? There seems to be a lot of discussion on brake upgrade so it would seem the "stock" brakes are lacking. There are quite a few different engine upgrades seemingly requiring a brake upgrade to go with the increased weight. One thing I have not heard of or read is a brake lock up problem. Is it possible to lock up the brakes on a 914 with a stock brake system? I have not been driving a teener for long and I don't mean to doubt anyone. I just want to get correct information.

Can stock brakes lock up the tire?

On a scale of 1 to 5 the improvement would be 0 over well maintained stock brakes with good quality pads. Plus, the BMW caliper must be machined to be used on our cars. Not an upgrade at all. THIS is an upgrade:

You can just barely see it but there is an aluminum caliper peeking out from that front Fuchs wheel. 4# lighter than the stock caliper and aluminum gives up heat faster.

Clean system, good tires, and better pads will do wonders. But at this point, it doesn't sound like you know the limits of the current system. Don't let a poorly bled system trick you into thinking you have bad brakes. And until you upgrade the engine to big power, don't bother with the BMW upgrade. Been there, did that, wasted money.

Yes. But I could lock up all four drums of my old Ford F-100 and those brakes sucked, so that can't be the only criteria. I know you can make the 914 brakes fade after 20 minutes of heavy braking coming down out of the mountains, so there's something to be said for vented rotors, too.

Locked up brakes do you very little good.

The Cap'n

I have to partially disagree. Orginally, I had good functioning stock front brakes and then moved to BMW320i front brakes and a 19mm master--there was an improvement in overall braking, but not monumental. Then of course I was stopping a heavier teener (SBC). BMW is not realy an upgrade.
Unless you get a pair of BMW calipers cheap, I wouldn't go that direction again...it's only a bandaid.

Recently, I just switched to the calipers I believe Rob was alluding to...aluminum brembos for 3inch struts. There is no comparision to how these work compared to stock or BMW calipers.

I do agree that for a stock car, well maintained stock brakes with some nice pads (i.e. Porterfield) is more than adequate for a street teener.

Going to the 320i front calipers isn't worth it IMHO, now going to Carrera fronts with vented discs is!

Might as well update or upgrade your whole front end and front brakes with a 911 suspension that most of us do. Its not that big of a job and if you can get the parts for a good price is a nice upgrade plus allows the use of 5 bolt Porsche wheels and adds some value to your car as well...not to mention poser points too

I got mine for very cheap from a 911T car that was rear ended and it made a nice improvement plus you get the slightly heavier torsion bars as well. I upgraded to new Koni shocks, new rotors later on, braided lines and new pads along with a 19mm master and its very nice....also added new BF goodrich tires and that was even better...eventually when I fix some other problems and make more progress I want to upgrade to Eric Shea's 3 inch alloy brake upgrade and some cross drilled rotors when funds allow.

I wasted money on the BMW brakes before going to the Brembo aluminum calipers. The Brembo calipers is one of the best upgrades I have done on a 914 and I feel money well spent.


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If I did it over again I'd stick with 911 struts with 3" caliper spacing and Brembos like Rob and others mentioned. I went with 3.5" and A calipers. I'm hauling around a ton of extra weight with little benefit until I save up the cash for aluminum S calipers. Matching my rears wont be pretty cost wise either.

Eric has a great thread on this. Do a search or someone can post a link.

BTW, "Beemer" refers to motorcycles, "Bimmer" to cars. I doubt motorcycle brakes would be much of an "upgrade" for your teener.

The Cap'n

I have a set of the BMW calipers on the front of my 914 right now...I cant say it was a totally wasted endeavor for a street set up, there was some "mild" improvement over stock...BUT...

A couple things to consider--the brake bias F to R is 'off'--you get more braking on the front than the back, not so noticeable on the street but go do a fast AX or TT and it gets scary fast when you feel like the back is going to come around on you. Also, you're still stuck with the solid rotors and really, that's the deal breaker--you are creating more heat with the front calipers and actually hit the fade point quicker...

The best solutions have been laid out already in this thread, there's lots of ways you can go with this but think long and hard as you're really putting your teener and possibly your life in the hands of the brake set up you choose...

I now have the same setup as Michael N posted above (sitting on my work bench ready to install) which is a 4 lug version of an early 911, vented is the only way to go to get an actual performance increase IMO...

If your F100 brakes lock up your wheels... their job is done. How could they suck? You would only need a larger contact patch to get better braking once your wheels lock (read: fatter tires).

If you don't know how to drive down a mountain without getting brake fade (in a car that should "never" experience brake fade other than "heavy" track duty) you really shouldn't be driving a 914 down a mountain.

Carrera calipers weigh 9+ frigg'n pounds EACH. I will guarantee you I would "Never" put those on one of my 914's. But wait, it gets better... 24mm Carrera vented rotors add an additional 4lbs. each. Welcome to nearly 20lbs. of additional UNSPRUNG weight to your 2000lb sports car. Guess what, the BMW caliper weighs almost the same!

Upgrade away gang... I'm enjoying the show.

P.S. My thoughts on "Why"people think they need "upgrades": Most of us enjoy modern cars on a daily basis. The wife has an E500 wagon with excellent brakes. My Cayenne has the largest set of calipers ever thrown on a standard road going Porsche (I found a small pony living in my right front). All of these brake systems are well designed and power assisted. Put your big toe on the pedal and the big car stops... really fast

It takes a few minutes to get use to the Cayenne after driving her car... now, imagine getting out of the Cayenne and going to a brake system from 1970, be it their top of the line 1970 914-6/GT model or a lowly (and lovely) 1970 914-4 (which has better brakes than anything in it's class!) Or... plop yourself into a 1970 Ford F-100. THINGS ARE GONNA FEEL DIFFERENT GANG.

Does this mean our brakes suck? All things being equal... NO. Your 2000lb 914 can still stop much faster than the 2012 7000lb. Suburban behind you so... keep that in mind.

Could they be better? Depends. To me, better means "stopping the car faster" and again, I'll go back to -- "If you can lock up your wheels with your current brakes, the answer is NO." Get bigger tires... you'll stop faster. Get better pads that allow you to modulate your pedal almost as well as an anti-lock devise... you'll stop faster. Learn "how" to brake/modulate and... you'll stop faster

Given enough money, time and engineering know-how, I'm sure someone could install my Cayenne calipers on a 914. It still won't stop any faster if the tire is sliding along on the pavement.

You mean upgrades like this, along with a 19mm MC on a 4cyl 2.0 is a wasted effort other than for eye candy?
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Wasted, no...had a setup similar to that on my old 6 conversion...the problem with it has already been stated as I'm sure you'll find out...You can brake way harder than your tires can hold, so be prepared for a learning curve.

I had to get used to not applying full brake in a quick stop or I was flat spotting tires...

Those pics are inducing some brake envy I'm sure...too much is not a bad problem to have...

That's looks like what I am thinking about for my SBC conversion. Going back to the original post, does this setup have any provision for a parking brake?

Totally agree... You can do what you like to your car and you can spend what you'd like of your money. Once you wheel stops spinning, you're brakes have done their job. Your stock 2.0 brakes would have done the job (for a lot less).

Bigger brakes are "Generally" not a bad thing to have. The problem lies in a more "Systematic" approach and how you've affected your original bias. I'd be willing to bet 9 out of 10 have not looked at it this way and have just gone and bolted the next biggest thing that someone recommends in a Pelican "How To" article.

Real world examples:

How many 914's have BMW fronts but nothing done to the rears?
How many 914's have A-Caliper (Carrera falls in this group) fronts but nothing done to the rears?
How many 914's have S-Caliper fronts but nothing done to the rears?
How many have 911 brakes all around and no handbrake?
How many have hydraulic line locks that are prone to failure when the system cools?

I applaud anyone who wants to put a well balanced "system" onto their car. The problem is, most of those systems (like the one shown for a 2.0 914) cost more than most 914 owners would spend for a 2.0 914.

Still saving up to fix this issue.

You wont find many people out there that know more about 914 braking than Eric Shea.

Answer's easy enough, Eric, it's the amount of control the brakes give you. Brakes aren't just full on-full off, any brake can lock the wheels, an F-100 or your 914, so no one doubts maximum capacity. The difference is what's in between, the modulation you alluded to, meaning the amount of control you have over those brakes before they lock up. That's what really separates that old F-150 from your 914, how easy or hard are they to modulate.

And of course you learn to modulate, like you learn everything else, but just like most other things some braking systems do it better, others not so good. As an example, have you ridden a modern sports bike, with those two huge rotors up front? Enormous amount of control in those brakes so you can brake right at the limit, carrying the back wheel skittering on the pavement for long distances. Hell, even morons like me can do stoppies on those things! Often successfully!

Compare that with my old Bonneville, back in the day. Exactly the same tire patch but no one back then even drempt of doing stoppies. Why? Those brakes were difficult to modulate, control, so nine times out of ten you'd lock up the front before you could get the rear end up. Same tire patch up front, the only difference is the control you get with those modern and "oversized" brakes. The sportbike guys call those brakes as having "long levers", because they're almost squishy, with a long travel between disc contact and locking the wheel. Small master cylinders obviously, combined with very large calipers and discs, two on one wheel.

I think that's everyone's goal, not more braking capacity to lock up the wheels, but more braking control before they lock.

O.K. lots of opinions...no measured data or real world test, like the one I had tonight. Just got the car back on the road with new struts, balls joints, pads, tie rod ends and a damn traffic light just had to turn red (you know the ones...the ones with the red light cameras at them). Well a full on panic stop, yup like Eric said, stock works! 'Cept one thing, the rather large pick up truck behind me kinda forced me (without contact) out into the intersection.
I don't AX (yet), so I won't be needing an upgrade anytime soon. The question was really in my head due to the post that had all the pictures of wrecked 914s. ALL the ones with front end damage! That kinda sent out a message. Thanks for all the views and examples.

Eric hits the nail on the head! I would like to add some thoughts though. Pretty much any vehicle (even that F150) can lock up the brakes once. The question becomes how many times in a row can you stop. Picture that truck coming down the mountain.....

A true "upgrade" really boils down to how many times you can stop repeatedly and that equates to heat absorbing and heat shedding capabilities since any brake system has a mechanical limit on both. The heat absorbing is mass and the heat shedding would be things like ventilated rotors. You need both to accomplish a true "upgrade"

Most people go from the brakes of a modern day car and jump into a 914 and feel the 914 sucks. It has nothing to do with capacity or the need for an "upgrade". Next they throw in a 19mm MC, get a FIRMER peddle but is more difficult to stop (peddle pressure goes up). It has everything to do with assist for the average person and the desire to have the modern day car feel. It's not going to happen without the assist!!! Try some different pads to change the coefficient of friction

So, when deciding if you need an upgrade ask yourself this.....Have my brakes EVER failed to easily stop the car? If the answer is no (all street guys), you are probably wasting your money to upgrade and an overhaul of a stock system will do wonders.

The track guys will most certainly feel loss of brakes. It's that heat issue that requires more mass and heat shedding ability. An upgrade for them typically adds little to the modern car feel but adds the ability to do it's job longer and more frequent.

Bottom line......If you think an "upgrade" is going to give the modern day car feel, you will be disappointing. If you want more "capacity" than upgrade away keeping in mind the need for both mass and heat shedding and the cost will be more weight....Are you sure you need it?

Hopefully this will save many some cash.....

A larger contact patch alone won't add to the amount of friction available for stopping. (Lbs per square inch goes down as the contact patch size increases.)

There needs to be more weight on the contact patch to get _any_ more friction. So the Carrera calipers and rotors actually help in that regard...

IMHO, stock brakes on a stock car, with some good pads (like Porterfields) are fine. Stock brakes are fine for AX. Once you start to track the car, they quickly become marginal. Any car with an upgraded motor and it starts to get dicey real quick. I've done stock brakes with a 1.7, built 2 liter, and finally a 2.3 liter -4 making around 175 HP. I can tell you that 140 mph into the bus stop at Watkins Glen with stock brakes is not really fun. Plus, you kill pads very quick, regardless of what you run (and the best for stock calipers are Raybestos from Porterfield Ent.).

I swtiched to Wilwoods all the way around and it made a world of difference with the car on the track. Granted, the brakes are about 5x bigger than stock, but it actually stops the car, they don't wear out in 2 sessions, and don't fade.

I'm running a 21mm MC, Wilwood forged Superlights front and rear - front with 1.75" pistons and rear with 1.38" pistons and a proportioning valve (almost full open). Required putting a new mount on the trailing arms, but completely worth it!

PHotos below including a comparison of the old front pads to the new.

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Until you beef up the power train, don't bother with the so-called "upgrades". As someone else said, just because you can, doesn't mean you should.

The stock brakes on a 914, in good working condition, are more than ample to haul down a 2000 lb 914. Even for autox, the stock brake system is great. And for track duty, better pads, high temp fluid, and a little ducting will more than do the job for a relatively stock 914.

Yes, just because you can lock up the tires isn't the only defining factor in a good brake system. Modulation is just as important, but that can be readily be effected by either pad changes, a different master cylinder, or both. Neither of which require custom machining in order to mate another brake caliper/rotor design to your car.

Make sure everything's in good condition, flush and bleed the brakes well, get new flex hoses, some good pads, and you'll be good to go for many years.

-Josh2

True in theory, not so true in practice. In theory, wider tires do not help with any grip. In practice, they do. That's because tires do not work on pure classical friction, they also have mechanical grip where bits of the rubber actually interlock with the irregularities in the pavement.

In general, larger tires will provide some extra grip. Softer tires definitely will.

Oh, but don't ignore the effect that wheel, tire, hub, and rotor weight! The heavier all of those parts are, and the further out the weight is from the center of rotation, the more work has to be done to stop them from spinning! You can see in some of the magazine tests that going with huge brakes and the equally-huge wheels and tires needed to fit around them actually INCREASES stopping distances!

But the point about repeated use is certainly valid, especially for cars on the track. Most especially for those with more speed potential than stock 914s.

--DD

My car came to me with 930 Turbo brakes all around. The front and rear have a simple T fitting. The rotors are about 1 inch thick, vented and drilled. I run 245/16's and 215/16's. The car stops on a dime. It can bring my V8 to a halt very quickly and I have never had any brake fade. I can lock up all 4 is I try but the brakes are so well balanced, I have to actually try to lock them. The MC is 19mm, I think. I could never afford to put these brakes on a 914. I bought the car for the same price as the callipers alone. I am very happy and I do a lot of spirited driving. My set up is not for everyone, but it works for me. I can hardly wait for PMB to start doing 930 callipers. I want Eric to make them pretty again