Help - Search - Members - Calendar
Full Version: Rear brakes and e-brake...
914World.com > The 914 Forums > 914World Garage
Pages: 1, 2
edhall
Hi guys, just joined as I've just got a 914. Need a little help with parts compatibility and wondered if anyone could help?

Car is a 74 914 with a 3.2 Carrera engine, 901 trans, and it stops with 911 SC vented rotors and calipers all round. Thing is, it doesn't have an emergency brake. The car was built in California but here in the uk it cannot be road legal without one.

Do I go 911 style drum in disc or 914 style ebrake on a calipers?

Thanks in advance
type47
I'd say get some 914 rear brakes from Eric Shea that have spacers for vented rotors. That way you can use stock 914 parking brake cables and not have to engineer the pull mechanism that you'd have to invent with 911 rear drums.
jimkelly
eric's site

http://www.pmbperformance.com/914-brakes.html

mepstein
PMB sells a 914-6 rear brake replica in aluminum that will bolt right on for $800
http://www.pmbperformance.com/catalog/item...676/9712726.htm
aharder
welcome.png
ChrisFoley
QUOTE(type47 @ Aug 15 2013, 06:44 AM) *

... not have to engineer the pull mechanism ...

The engineering has already been done. sunglasses.gif
Tangerine Racing Brakes Page - Adapter Cables
green914
welcome.png
Eric_Shea
For all of the money and time you would spend fitting a 911 handbrake solution you could go with a proper factory solution and bolt up factory handbrake cables for less money and less hassles. I know because I do both. I've built probably 12 complete suspensions using 911 components.

This is, in fact, why we went forward developing the VB914-6 and VB914-6/GT calipers. It's now cheaper to do it right:

If you're a stickler for originality, I have 3 pair of stock 914-6 calipers available @ $1,200.00 per pair:
IPB Image

We also have the VB914-6 alloy calipers as mentioned above @ $799.00 per pair:
IPB Image

The 914-6/GT versions would bolt up to your rear vented rotors for $899.00 per pair:
IPB Image

All of these have the same 38mm piston size and the same FSMI D31 pad size your 911 rear calipers have.
ChrisFoley
QUOTE(Eric_Shea @ Aug 15 2013, 12:15 PM) *

This is, in fact, why we went forward developing the VB914-6 and VB914-6/GT calipers. It's now cheaper to do it right:

I like this route best. You get a lot more braking power than 914-4 calipers and no alterations required smile.gif
You won't beat that deal doing the 911 e-brake conversion unless you find a pair of 911 trailing arms with all the components, including the shoes, in usable condition for cheap $$.
andys
QUOTE(Racer Chris @ Aug 15 2013, 07:36 AM) *

QUOTE(type47 @ Aug 15 2013, 06:44 AM) *

... not have to engineer the pull mechanism ...

The engineering has already been done. sunglasses.gif
Tangerine Racing Brakes Page - Adapter Cables


Chris,

On your cable adapter, do you remove one half of the "butterfly" actuator on the brake shoe's?

Andys
ChrisFoley
QUOTE(andys @ Aug 15 2013, 01:25 PM) *

Chris,

On your cable adapter, do you remove one half of the "butterfly" actuator on the brake shoe's?

Andys

Yes, that is correct.
It wouldn't work if the "floating" style cable installation was used.
Trekkor
http://www.rockauto.com/ has several options.

914-6 rears are $100 each, for example:

http://www.rockauto.com/getimage/getimage....es/14137580.jpg

part # 14137580

1970 914-6


KT
Eric_Shea
You'll have to read up on that. there's a core charge.
Trekkor
http://www.oreillyauto.com/site/c/search/B...tkeyword=brakes

O'Reilly has quite a few offerings as well.


KT
worn
QUOTE(Eric_Shea @ Aug 15 2013, 09:15 AM) *

For all of the money and time you would spend fitting a 911 handbrake solution you could go with a proper factory solution and bolt up factory handbrake cables for less money and less hassles. I know because I do both. I've built probably 12 complete suspensions using 911 components.

This is, in fact, why we went forward developing the VB914-6 and VB914-6/GT calipers. It's now cheaper to do it right:

All of these have the same 38mm piston size and the same FSMI D31 pad size your 911 rear calipers have.


Hi Eric,
I have the 911 SC brake parts in hand and can handle the parking brake conversion. Would you comment on the differences between those vented brakes and the reproduction 914-6 brakes? I know what I have because I also have a 911SC, but I don't have familiarity with the original 914-6 because I am making it from a 914-4 as a starting point.
Thanks, and also thanks for doing all this stuff for us. Do you get to pour the metal?
Cap'n Krusty
[quote name='Trekkor' date='Aug 15 2013, 12:33 PM' post='1909693']
http://www.oreillyauto.com/site/c/search/B...tkeyword=brakes

O'Reilly has quite a few offerings as well.


KT
[/quot

To all those using brake parts sourced from Rockauto, O'Reillys, your FLAPS, and other non-P-car specialist sources: Please don't drive on streets where I, or anyone I know or like, may be driving. I don't care if you choose to use crap for your brakes, but I DO care that you might hit me when they inevitably fail..............

Thank you for your time ................. The Cap'n
Cap'n Krusty
QUOTE(edhall @ Aug 14 2013, 11:02 PM) *

Hi guys, just joined as I've just got a 914. Need a little help with parts compatibility and wondered if anyone could help?

Car is a 74 914 with a 3.2 Carrera engine, 901 trans, and it stops with 911 SC vented rotors and calipers all round. Thing is, it doesn't have an emergency brake. The car was built in California but here in the uk it cannot be road legal without one.

Do I go 911 style drum in disc or 914 style ebrake on a calipers?

Thanks in advance


FWIW, the conversion wasn't legal in California, either. Nor in any state in the USA.

The Cap'n
Trekkor
QUOTE(Cap'n Krusty @ Aug 15 2013, 01:57 PM) *



To all those using brake parts sourced from Rockauto, O'Reillys, your FLAPS, and other non-P-car specialist sources: Please don't drive on streets where I, or anyone I know or like, may be driving. I don't care if you choose to use crap for your brakes, but I DO care that you might hit me when they inevitably fail..............

Thank you for your time ................. The Cap'n



I'm just not hearing about brake failures anywhere in the news.
People hitting the gas instead of the brakes, yes.


KT
Eric_Shea
QUOTE(worn @ Aug 15 2013, 01:33 PM) *

QUOTE(Eric_Shea @ Aug 15 2013, 09:15 AM) *

For all of the money and time you would spend fitting a 911 handbrake solution you could go with a proper factory solution and bolt up factory handbrake cables for less money and less hassles. I know because I do both. I've built probably 12 complete suspensions using 911 components.

This is, in fact, why we went forward developing the VB914-6 and VB914-6/GT calipers. It's now cheaper to do it right:

All of these have the same 38mm piston size and the same FSMI D31 pad size your 911 rear calipers have.


Hi Eric,
I have the 911 SC brake parts in hand and can handle the parking brake conversion. Would you comment on the differences between those vented brakes and the reproduction 914-6 brakes? I know what I have because I also have a 911SC, but I don't have familiarity with the original 914-6 because I am making it from a 914-4 as a starting point.
Thanks, and also thanks for doing all this stuff for us. Do you get to pour the metal?


SC parts will be even more difficult to fit. The bearing is larger and the hole diameter won't line up with a 914 control arm.

I think you're asking for a comparison of the SC rear caliper you have an the 914-6 and or our reproduction so, here goes.

Same piston size 38mm
Same pad size FSMI D31
Nose section is cast from the same casting, just machine out the hole for the adjuster
914-6 variants have adjustable pistons/pad clearance
914-6 variants have integrated handbrake
Our reproductions are under 3lbs each saving a total of 8lbs.
Fastener size on the 911 and 914-6 caliper is M7. Our reproduction is M8
Stock is cast steel
Ours is cast aluminum

I can barely pour my own beer let alone molten metal blink.gif
r_towle
Mid 90's vw passat looks like it may work on vented rotors with possibly an adapter to make the caliper mount correctly.

It has a cable actuated e-brake
jcd914
QUOTE(r_towle @ Aug 15 2013, 07:01 PM) *

Mid 90's vw passat looks like it may work on vented rotors with possibly an adapter to make the caliper mount correctly.

It has a cable actuated e-brake


I think all the mid 90s VW/Audi rear calipers are single piston floating calipers.
So you would need the single piston to be larger that the 38mm 914/911 pistons to get the same clamping force.
I don't know piston sizes on any of them.
They are good brakes, durable, just nothing spectacular.

Jim
Elliot Cannon
I have PMB's alloy 914/6 calipers on my car. Very easy installation. So far, very happy with them. Good product, excellent support. welcome.png
Socalandy
PMB 914-6GT calipers on my ride with Stock E-brake cables an lines installed in about 20 min. per wheel biggrin.gif

edhall
This is all great stuff. Thanks! I'll spend a bit of time digesting all this, but the 914-6 calipers looks to be the way to go.
DBCooper
QUOTE(Trekkor @ Aug 15 2013, 06:31 PM) *

QUOTE(Cap'n Krusty @ Aug 15 2013, 01:57 PM) *



To all those using brake parts sourced from Rockauto, O'Reillys, your FLAPS, and other non-P-car specialist sources: Please don't drive on streets where I, or anyone I know or like, may be driving. I don't care if you choose to use crap for your brakes, but I DO care that you might hit me when they inevitably fail..............

Thank you for your time ................. The Cap'n



I'm just not hearing about brake failures anywhere in the news.
People hitting the gas instead of the brakes, yes.


KT

That's because there haven't been any. If there had been the National Traffic Safety Administration would be all over it, as would every plaintiff's attorney in the country, not to mention those company's own attorneys and insurance carriers. I think the Cap'n is exaggerating (Krustily) to make a point.


monkeyboy
When I first picked up my 914 years ago, the manager told me he could get me all the brake parts I needed. I eventually cancelled my order as they were on permanent backorder.

They may show on the website, but I doubt they actually can get them.

Not that I would go that route again.
worn
[quote name='Cap'n Krusty' date='Aug 15 2013, 12:57 PM' post='1909733']
[quote name='Trekkor' date='Aug 15 2013, 12:33 PM' post='1909693']
http://www.oreillyauto.com/site/c/search/B...tkeyword=brakes

O'Reilly has quite a few offerings as well.


KT
[/quot

To all those using brake parts sourced from Rockauto, O'Reillys, your FLAPS, and other non-P-car specialist sources: Please don't drive on streets where I, or anyone I know or like, may be driving. I don't care if you choose to use crap for your brakes, but I DO care that you might hit me when they inevitably fail..............

Thank you for your time ................. The Cap'n
[/quote]

I understand Capn', but I have to point out that the odds of you being hit by a Porsche with OReilly brakes, compared to any other car with OReilly parts are probably similar to shark attack and the lotto cashing in. Think Escalade or Tacoma when you worry. Or perhaps an 80's muscle car. Ever see one of those at Auto Zone? Personally I would rather take my chances with a 914 since I only see them at club meetings. poke.gif bye1.gif
worn
[/quote]

SC parts will be even more difficult to fit. The bearing is larger and the hole diameter won't line up with a 914 control arm.

I think you're asking for a comparison of the SC rear caliper you have an the 914-6 and or our reproduction so, here goes.

Same piston size 38mm
Same pad size FSMI D31
Nose section is cast from the same casting, just machine out the hole for the adjuster
914-6 variants have adjustable pistons/pad clearance
914-6 variants have integrated handbrake
Our reproductions are under 3lbs each saving a total of 8lbs.
Fastener size on the 911 and 914-6 caliper is M7. Our reproduction is M8
Stock is cast steel
Ours is cast aluminum

I can barely pour my own beer let alone molten metal blink.gif
[/quote]
I have the whole SC front suspension with spindles, so I think that should work - eh?

So similar characteristics in terms of braking, but the SC would be a PITA in terms of fiddling and also heavy. You are tempting me. I pour aluminum in the driveway as an amusement, but have bought more safety equipment since my son got burned with a little tiny piece. Thanks Eric!
914_teener
[quote name='worn' date='Aug 16 2013, 10:39 AM' post='1910295']
[/quote]

SC parts will be even more difficult to fit. The bearing is larger and the hole diameter won't line up with a 914 control arm.

I think you're asking for a comparison of the SC rear caliper you have an the 914-6 and or our reproduction so, here goes.

Same piston size 38mm
Same pad size FSMI D31
Nose section is cast from the same casting, just machine out the hole for the adjuster
914-6 variants have adjustable pistons/pad clearance
914-6 variants have integrated handbrake
Our reproductions are under 3lbs each saving a total of 8lbs.
Fastener size on the 911 and 914-6 caliper is M7. Our reproduction is M8
Stock is cast steel
Ours is cast aluminum




I can barely pour my own beer let alone molten metal blink.gif
[/quote]
I have the whole SC front suspension with spindles, so I think that should work - eh?

So similar characteristics in terms of braking, but the SC would be a PITA in terms of fiddling and also heavy. You are tempting me. I pour aluminum in the driveway as an amusement, but have bought more safety equipment since my son got burned with a little tiny piece. Thanks Eric!
[/quote]



shades.gif
worn
[/quote]



shades.gif
[/quote]

Well, yeah you are right. But he did get training in engineering school that I shelled out a lot of money for. There he poured a little V8 block.
Trekkor
http://www.cardone.com/products/brakes

I trust this company.
I have used many of their parts.

Their calipers are on my race car.

They have been in business since 1970~


KT
Eric_Shea
QUOTE
I have the whole SC front suspension with spindles, so I think that should work - eh?

So similar characteristics in terms of braking, but the SC would be a PITA in terms of fiddling and also heavy. You are tempting me. I pour aluminum in the driveway as an amusement, but have bought more safety equipment since my son got burned with a little tiny piece. Thanks Eric!


Lets see if we can get this quote thing right... biggrin.gif

The SC front would work. If it's for street and occasional autocross, i would just use the struts and not the A-Arms and crossmember. Keep in mind, the A-Caliper associated with that is the heaviest caliper ever used on a Porsche.

The rears are essentially the same. Same piston same pad and parts of the calipers even come out of the same mold.

Yes, the rear handbrake mechanism is more trouble than it's worth. I would get about 1/2 way through grinding one arm before I decided to go 914-6 calipers in the rear but that's just me. Then you have to fit the parking brake, have the holes elongated etc. A 70-73 handbrake assembly would bolt on with more grinding and more welding and custom cables etc. Again, I would opt for a 914-6 caliper that bolts on vs. all of that.
worn
QUOTE(Eric_Shea @ Aug 16 2013, 12:58 PM) *

The SC front would work. If it's for street and occasional autocross, i would just use the struts and not the A-Arms and crossmember. Keep in mind, the A-Caliper associated with that is the heaviest caliper ever used on a Porsche.


So, I am thinking you have a set of great rear brakes, but what do I want in front where the weight reads up? If the a calipers are too heavy, what is better? I just looked at your site and saw rears. Oh that is tempting given the smilies we have available.
Eric_Shea
I like S-Calipers. But they're expensive. Otherwise, stay with a 3" strut an go Brembo. At 4lb 6oz they are the lightest.

http://www.pmbperformance.com/catalog/item...645/6862358.htm
ChrisFoley
QUOTE(Eric_Shea @ Aug 16 2013, 11:20 PM) *

... stay with a 3" strut an go Brembo. At 4lb 6oz they are the lightest.

http://www.pmbperformance.com/catalog/item...645/6862358.htm

You've been busy. That's an excellent choice!
beerchug.gif
Steve
Eric's solution is the way to go. IMHO, to go with 911 rear e-brakes you need to weld a hefty stopping brace to the trailing arm, let alone the additional cable mods. I had Wes (rip) weld some thick braces to my trailing arm. Similar size and structure to a 911 trailing arm. I then used early 911 e-brakes and Boxster rear brakes. For the cables, I used modified 914 clutch cables. It only pulls from one side, but works fine. Regarding the brace there is a bolt on available, but I am curious how strong it is in case of an emergency. If your going 60 plus miles an hour and yank on the emergency brake, will it rip off? The brace prevents the shoes from ripping apart and spinning on the axle. I only went with this solution because Eric's solution wasn't available at the time.
Click to view attachment
Click to view attachment
Click to view attachment
ChrisFoley
QUOTE(Steve @ Aug 18 2013, 10:57 AM) *

Eric's solution is the way to go. IMHO, to go with 911 rear e-brakes you need to weld a hefty stopping brace to the trailing arm, let alone the additional cable mods. I had Wes (rip) weld some thick braces to my trailing arm. Similar size and structure to a 911 trailing arm. I then used early 911 e-brakes and Boxster rear brakes. For the cables, I used modified 914 clutch cables. It only pulls from one side, but works fine. Regarding the brace there is a bolt on available, but I am curious how strong it is in case of an emergency. If your going 60 plus miles an hour and yank on the emergency brake, will it rip off? The brace prevents the shoes from ripping apart and spinning on the axle. I only went with this solution because Eric's solution wasn't available at the time.

911 and 914 cable operated braking mechanisms are just parking brakes.
They really aren't designed to handle the loads imposed in an emergency braking situation. Additionally, a true emergency brake handle wouldn't lock in position, which would be dangerous.

My 911 "e-brake" conversion kit is a weld on solution which works just fine, but I wholeheartedly endorse using Eric's calipers.
They simply bolt on and work just as the factory calipers did, without additional modification. Its sensible and economical. smile.gif
Steve
I agree and if someone wanted to go down the 911 e-brake path yours is the best solution, however on steep hills like in San Francisco or where I live, I use the e-brake to prevent the car from rolling backward. Also 30 years a go in a different 914 i had a catastrophic brake failure where the brake pedal went to the floor and my only choice was to hold the button in on the e-brake handle to stop. Scared the crap out of me. Funny how the 914 and 911 manual call it a hand brake. Maybe its a German thing!!
Jeff Hail
QUOTE(Steve @ Aug 18 2013, 08:57 AM) *

Eric's solution is the way to go. IMHO, to go with 911 rear e-brakes you need to weld a hefty stopping brace to the trailing arm, let alone the additional cable mods. I had Wes (rip) weld some thick braces to my trailing arm. Similar size and structure to a 911 trailing arm. I then used early 911 e-brakes and Boxster rear brakes. For the cables, I used modified 914 clutch cables. It only pulls from one side, but works fine. Regarding the brace there is a bolt on available, but I am curious how strong it is in case of an emergency. If your going 60 plus miles an hour and yank on the emergency brake, will it rip off? The brace prevents the shoes from ripping apart and spinning on the axle. I only went with this solution because Eric's solution wasn't available at the time.
Click to view attachment
Click to view attachment
Click to view attachment


I miss Wes. Good man down.
Steve
agree.gif
Wes did all that work on my trailing arms and would not take any money for it, just lunch at Sharkey's. People like him make me try harder to be more positive and always do what is right!!
Eric_Shea
Here's my take; many think I'm a big brake hater, which I'm not. I simply don't think enormous brakes are needed on a 914. It's a tiny lightweight car and an S-Caliper or a 908 caliper is just fine. That's what brings my car to a halt and nearly every single 914 in HSR series racing. I kid you not, if you're get a chance to see Frank Beck of Phoenix drive his 914 at speed you will get tears in your eyes.

My concerns usually are twofold:

1. A mis-engineered system. Big brakes up front and nothing in the rear or worse, big brakes in the rear and not much up front (the old "put and early 914 front caliper on the rear" trick). The ideal factory balance with fancy calculations and all comes to about 1.6:1 front to rear... regardless of how big you want to go.

2. People ditching the pressure regulator on street cars. It's the first anti-lock brake device and it belongs in you car.

So... if you want to put 930 or 996 calipers on your 914, feel free. You will have amazing brakes. They may be difficult to modulate at first but you should be able to get use to that. That's when Chris' system pays off. It is the most "stout" of all 911 e brake solutions and as mentioned by the previous poster, it should handle heavy duty handbrake use. If you read Vic Elford's Performance driving handbook, he uses the handbrake to bust the back-end loose in corners when rally driving. Chris's solution is the only one I would trust to do that as he has a very strong piece of metal welded to the arms for the shoes to pivot on.

Nice balanced early system? Use 911 calipers and struts up front with 914-6 calipers in the rear.

Nice balanced big-big brake system (930 front and rear as an example... Remember 1.6:1 and a good "system" approach) - the CFR kit is the only way I would go to get a handbrake.
Jeff Hail
QUOTE(Eric_Shea @ Aug 18 2013, 12:33 PM) *

Here's my take; many think I'm a big brake hater, which I'm not. I simply don't think enormous brakes are needed on a 914. It's a tiny lightweight car and an S-Caliper or a 908 caliper is just fine. That's what brings my car to a halt and nearly every single 914 in HSR series racing. I kid you not, if you're get a chance to see Frank Beck of Phoenix drive his 914 at speed you will get tears in your eyes.

My concerns usually are twofold:

1. A mis-engineered system. Big brakes up front and nothing in the rear or worse, big brakes in the rear and not much up front (the old "put and early 914 front caliper on the rear" trick). The ideal factory balance with fancy calculations and all comes to about 1.6:1 front to rear... regardless I how big you want to go.

2. People ditching the pressure regulator on street cars. It's the first anti-lock brake device and it belongs in you car.

So... if you want to put 930 or 996 calipers on your 914, feel free. You will have amazing brakes. They may be difficult to modulate at first but you should be able to get use to that. That's when Chris' system pays off. It is the most "stout" of all 911 e brake solutions and as mentioned by the pervious poster, it should handle heavy duty handbrake use. If you read Vic Elfords Performance driving handbook, he uses the handbrake to bust the backend loose in corners when rally driving. Chris's solution is the only one I would trust to do that as he has a very strong piece of metal welded to the arms for the shoes to pivot on.

Nice balanced early system? Use 911 calipers and struts up front with 914-6 calipers in the rear.

Nice balanced big-big brake system (930 front and rear as an example... Remember 1.6:1 and a good "stysem" approach) - the CFR kit is the only way I would go to get a handbrake.



Going back to the 11 parking brake Eric, did you ever weld the rotation limiting 40mm bracket on the arms or did you leave them on the backing plates? Reason I ask is longevity. Recently inspected a 14 with 11 parking brakes and noticed the backing plates were cracked from fatigue where the owner welded the 40mm limiter to the backing plate. Thinking about it as long as it is used as a parking brake not a major issue as the shoe's won't twist inside the rotor drum -BUT if in an emergency situation required them to be used as a stopping brake they would well you know....
Eric_Shea
I decided to go with the stock solution and sold those. The way I did it would only work as a parking brake. Not good for an emergency brake solution. Again, that's exactly why the CFR solution is best for those who want big brakes beyond the 914-6 and S/A-Caliper solution.

The last customer 911 solution we did utilized the CRF system. Any future ones will as well.
Jeff Hail
QUOTE(Eric_Shea @ Aug 18 2013, 01:02 PM) *

I decided to go with the stock solution and sold those. The way I did it would only work as a parking brake. Not good for an emergency brake solution. Again, that's exactly why the CFR solution is best for those who want big brakes beyond the 914-6 and S/A-Caliper solution.

The last customer 911 solution we did utilized the CRF system. Any future ones will as well.



Thanks Eric
Steve
I am also running stock Boxster brakes up front. All the caliper adapters came from Rich Johnson. I am using a T instead of the stock proportioning valve.
hide.gif
I am also using a 19mm master cylinder. I am quite happy with the brakes.
I have driven the car in drivers training courses and in multiple auto-crosses and if I slam my foot on the brakes the fronts will eventually lock up first. I have never had the rears lock up (so far)...


ChrisFoley
QUOTE(Eric_Shea @ Aug 18 2013, 02:33 PM) *

...
I simply don't think enormous brakes are needed on a 914. It's a tiny lightweight car ...

agree.gif
My race car still has stock 914-4 rears.
With my bias control I can still adjust it so the rears lock up first (not that I would want it that way unsure.gif ).
Thats with slicks more than 10" wide.
chad newton
QUOTE(mepstein @ Aug 15 2013, 05:25 AM) *

PMB sells a 914-6 rear brake replica in aluminum that will bolt right on for $800
http://www.pmbperformance.com/catalog/item...676/9712726.htm

Will they bolt on vented rotor though?
Eric_Shea
Read post #8 in this thread. (or post #22... or post #23)
chad newton
QUOTE(Eric_Shea @ Aug 18 2013, 09:19 PM) *

Read post #8 in this thread. (or post #22... or post #23)

I missed that. I had no idea the gt's ran vented rotors. Cool.
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.
Invision Power Board © 2001-2024 Invision Power Services, Inc.