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Brake upgrade for 4 stud wheels
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indi9xx  



Joined: 01 Nov 2003
Posts: 83
Location: Bournemouth, UK

PostPosted: Wed Apr 14, 2004 3:17 am    Post subject: Brake upgrade for 4 stud wheels Reply with quote

Anyone out there know of ways of upgrading the 924 4 stud brakes, without going over to the 5 stud wheels.

We have a customer who has just brought a set of 17 inch wheels, then comes to us asking for a brake upgrade... we explained that he should have had the 944 brake conversion, then gone shopping for wheels... but what is done is done..

So, any ideas/options?

We are at a loss, except for maybe cross drilling the front disks and grooving the rear drums.

We would go to the effort of designing something, but this car is a bit of a one off, most people would have gone for the 5 stud approach... ho hum

Jon Mitchell
Independent Porsche Specialists
Bournemouth, UK
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Mikri184  



Joined: 12 Sep 2003
Posts: 746
Location: Ferndale, WA

PostPosted: Wed Apr 14, 2004 3:39 am    Post subject: brake upgrades Reply with quote

What your customer needs to do is contact a VW supplier and buy the disc brake conversion for a late super beetle front and rear and have them redrill the rotors for the lug pattern he needs, spacers may still need to be installed. Cost in U.S is about $600 plus shipping.
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-nick  



Joined: 16 Nov 2002
Posts: 2699
Location: Cambridge, MA

PostPosted: Wed Apr 14, 2004 4:11 am    Post subject: Reply with quote

Or you can just get him/her some better pad/shoe compounds. I think Hawk makes some for the 4-lug brakes. You can convert to 5-lug for less than $600. Also, there's no reason to crossdrill/slot the rotors&drums. That's just going to reduce the small surface area you already have. It's really a marketing gimmick. It will only help in the rain.

-nick
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indi9xx  



Joined: 01 Nov 2003
Posts: 83
Location: Bournemouth, UK

PostPosted: Wed Apr 14, 2004 4:56 am    Post subject: Reply with quote

For this guy, he insists on sticking with 4 stud... we are thinking about seeing what we can do to convert 5 stud hubs to 4 stud, but due to the aluminium hubs, its not looking good. Which is a shame, because we have loads of kits on the shelf ready and waiting to convert 924's to 5 stud 911SC/944 brakes..We may find something we can do.. but alas, this guy insists on sticking with the 4 stud patern (

We have found some improvement of limiting brake fade on 924's with cross drilling, as it seems to help disipate the gas build up between disk and pad during braking and assist cooling a little. But we really want to improve the amount of braking force that can be applied.. so some bigger calipers and larger vented disks would be just the ticket.

Jon Mitchell
Independent Porsche Specialists
Bournemouth, UK
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ponchojuan  



Joined: 20 Jul 2004
Posts: 51
Location: Boston, MA

PostPosted: Tue Aug 24, 2004 12:21 am    Post subject: Reply with quote

Jon, I'm sure you solved this issue, but here is a possible link for future reference. EMPI makes conversion kits for VW. The stud pattern may need to be redrilled and tapped, or you might be able to get rotors that fit the porsche pattern from them.

cip1.com sells these kits for around US$300.

http://www.empius.com/d/discbrakekits.html
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Andrew NZ  



Joined: 22 Jun 2004
Posts: 744
Location: New Zealand

PostPosted: Tue Aug 24, 2004 8:22 am    Post subject: Reply with quote

How about machining the edge off the drum to provide a plate to slide Peugeot rear disks over (same stud pattern). All you'd have to do is make some brackets for the Peugeot callipers then. I've done similar things with offroaders, but not sure if it would work on a porsche. What do you think?
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gohim  



Joined: 02 Nov 2002
Posts: 4459
Location: Rialto, CA

PostPosted: Tue Aug 24, 2004 5:07 pm    Post subject: Reply with quote

The biggest problem with the rear drum brakes is the fact that they are not self-adjusting, and the rapid wear of the shoes makes for a mushy pedal and poor braking every thousand miles.

Machining off the edges of the brake drum and refitting a disk over the top is an interesting idea. The question is, will the French rotor friction surface end up in the right plane for the caliper (assuming you use the 924/931/944 rear caliper). Is the French rotor the right size to work with the Porsche 11.2 rotor caliper? What do you do for a parking brake?

The other problem would be the front to rear brake balance. If you keep the solid front rotors, I would expect that the front to rear brake balance to be off. Need a proportioning valve?
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Andrew NZ  



Joined: 22 Jun 2004
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Location: New Zealand

PostPosted: Wed Aug 25, 2004 9:17 am    Post subject: Reply with quote

You'd have to use the peugeot calipers as well, which have a built in hand brake. I'd also looked at the Audi discs, but the peugeot ones apear to have a better offset to be able to fit the callipers in etc.

How are the calipers mount on the porsche set up? are they just bolted to the four bolts that hold the drum backing plates on, or are there additional brackets?

I've been wondering about the balance too, infact this is the thing thats stopped me getting too serious about the idea just yet! Anyone want to try it and let me know if it works?
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CorsePerVita  



Joined: 25 Jul 2008
Posts: 1992
Location: Redmond, Oregon

PostPosted: Sat Jun 20, 2009 8:35 am    Post subject: Reply with quote

ponchojuan wrote:
Jon, I'm sure you solved this issue, but here is a possible link for future reference. EMPI makes conversion kits for VW. The stud pattern may need to be redrilled and tapped, or you might be able to get rotors that fit the porsche pattern from them.

cip1.com sells these kits for around US$300.

http://www.empius.com/d/discbrakekits.html


So which kit, this is a very old link and their site is up.

I'm trying to figure out if i really want to go with a 944 brake setup, or convert it to a 4 lug disc setup on the back. The new link for their kits is http://www2.cip1.com/ProductDetails.asp?ProductCode=ACC%2DC10%2D4126%2DKT

I'm trying to figure out what my options are on converting this over. I have no issue drilling and getting stuff configured and all. Just want to make sure I'm digging in and getting all the info right.

Are there any other 4 lug conversions that have been quite successful?

PS: The empius page is - http://www.empius.com/2009_catalog/empi2009_pg170.html

Also, what TO DO with balance in regards to proportioning valve.
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haroldk  



Joined: 24 Nov 2008
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PostPosted: Sat Jun 20, 2009 11:41 am    Post subject: Reply with quote

I was actually going to be looking into doing a conversion using the drums and front rotors as hub flanges as described above. I was thinking of trying Ford parts since I've got a good supply of those. With the right adaptor parts, I'm sure something could be made to fit. That has the added benefit of not needing to pull an axle nut every time you want to change a rotor.

I'd like to go this route since I've got 6 sets of wheels, all told, in 4x108 from my other cars. Since the other wheels I have are between 35mm and 48mm offset, adding thickness to the flange face would only mean I'd need a thinner spacer to use the wheels.

Frankly I was a little surprised I haven't seen this done yet.
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Andrew NZ  



Joined: 22 Jun 2004
Posts: 744
Location: New Zealand

PostPosted: Sat Jun 20, 2009 3:43 pm    Post subject: Reply with quote

I did it a few years ago with the Peugeot parts, but when I changed to 944 bits the difference was huge.

In my opinion it's not worth wll thw messing around - just get the 944 setup!
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CorsePerVita  



Joined: 25 Jul 2008
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PostPosted: Sat Jun 20, 2009 4:12 pm    Post subject: Reply with quote

Andrew NZ wrote:
I did it a few years ago with the Peugeot parts, but when I changed to 944 bits the difference was huge.

In my opinion it's not worth wll thw messing around - just get the 944 setup!


has anyone ever put down /exactly/ what you need to do a 944 swap? I've seen "Need to swap the suspension and transmission, etc..." and have also heard "JUst this and that" and "THis and that, and a tranny + this and even torque tube."

SO which is it?

So say I /just/ want to convert to disc, go with a 944 setup, i have a 77' just exactly /what/ parts do i need? That has been my largest confusion. If anyone is interested in answering i can start a totally new thread so i'm not derailing this one.
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- 1977 Porsche 924 2.0 N/A (Trackday Project)
- 1979 Porsche 924 2.0 N/A (The other daily)
- 1980 Porsche 931 (Daily)
- 1987 Lamborghini Jalpa
- 1999 Ducati 900SS
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Scorpio  



Joined: 05 Jul 2007
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Location: Brisbane, Australia

PostPosted: Sat Jun 20, 2009 5:25 pm    Post subject: Reply with quote

CorsePerVita wrote:
Andrew NZ wrote:
I did it a few years ago with the Peugeot parts, but when I changed to 944 bits the difference was huge.

In my opinion it's not worth wll thw messing around - just get the 944 setup!


has anyone ever put down /exactly/ what you need to do a 944 swap? I've seen "Need to swap the suspension and transmission, etc..." and have also heard "JUst this and that" and "THis and that, and a tranny + this and even torque tube."

SO which is it?

So say I /just/ want to convert to disc, go with a 944 setup, i have a 77' just exactly /what/ parts do i need? That has been my largest confusion. If anyone is interested in answering i can start a totally new thread so i'm not derailing this one.


chances are the next few responses will be links to past threads....im a little confused aswell but mainly coz the brake upgrade has been something ive purposefully avoided...something about making new hardlines really threw me off
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haroldk  



Joined: 24 Nov 2008
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PostPosted: Sat Jun 20, 2009 10:37 pm    Post subject: Reply with quote

Andrew NZ wrote:
I did it a few years ago with the Peugeot parts, but when I changed to 944 bits the difference was huge.

In my opinion it's not worth wll thw messing around - just get the 944 setup!


To be fair, it may have been something to do with the parts you chose, as well. I'd likely be going with dual piston front calipers and vented rotors of a larger size all the way around. There's no reason the stock 944 parts should be the end-all be-all of brakes.
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fiat22turbo  



Joined: 18 Jan 2006
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Location: Portland, OR

PostPosted: Sun Jun 21, 2009 4:36 am    Post subject: Reply with quote

the answer is:

Depends.....


You have two options:

Keep the steel rear trailing arms and stock transmission and use early 944, 924S or 924 turbo rear disc brakes from a car with steel rear control arms. You'd need the rear disc calipers (which are all the same) discs, the caliper adapters (backing plates), the hubs, e-brake cables and hoses.

If you want to use the aluminum rear trailing arms, you'd need to change the suspension carrier, transmission, transmission mount, torque tube, axles, and clutch (a 924 turbo bellhousing, starter, hydraulic clutch conversion might be a good idea at this point as well)

The entire rear end has to be changed because the later model arms don't fit the early style rear suspension carrier and the later carrier doesn't have the ears to hold the 915 transmission. So that means the transmission, the mount, the torque tube and the clutch (to mate the 924 NA to the 944 splines) Basically, got a parts 944 or 924S?

The master cylinder should be changed and the brake line routing needs to be changed as well for both types of solutions. Because the balance is changed and the brake system is split differently. Luckily that is one change that isn't as bad as it sounds.

Or you can read this thread posted by Ideola:

http://www.924board.org/viewtopic.php?p=218957#218957
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