Porsche Brake Project

[adamski]

I'm upgrading my brakes to Porsche brakes at the moment, so I thought I would document the work on here.
First up - front and rear calipers from eBay. They are just back from the paint shop:

 

[adamski]

So the plans are to fit the following:
- Front and rear boxster 996 brakes (using kits from Transporterhaus)
- 16 inch fuchs (these should be back from the restorer soon)
- air shocks up front
- some tweaks to my front beam

Originally I was going to go for 944 brakes all round. Then I got chatting with a few people including Alex from Transporterhaus. So these will be up for sale (except the front hubs):

 

[Heebee_GB]

Excellent. This will be really usefull. *bookmarks thread*

 

[moler]

x2

 

[Haveacamper]

hey mate,

what are you going to be going for on the rear? will be interesting thread this

 

[adamski]

For the rear I'm planning on the Transporterhaus rear kit

http://transporterhaus.de/index.php?option=com_content&task=view&id=215&Itemid=155" onclick="window.open(this.href);return false;

For the front I will be getting their adaptors for the brazillan spindles as I have a K&L narrowed beam with brazilian bits, spindles I think (not sure of the technical term, someone help me out!). I had this done at T2D a couple of years back.

The part number for the callipers are:

Front:
996 351 421
996 351 422

Rears:
996 352 421
996 352 422

In terms of sourcing these callipers you can try breakers or ebay. I went with the ebay route and it was very reasonable. Breakers can be a little more (£300+VAT). A good porsche breakers are Douglas Valley breakers (http://www.douglasvalley.co.uk" onclick="window.open(this.href);return false. Although breakers can be difficult with returns if you get the wrong parts.

I then had the callipers painted by the porsche garage local to me (Chelsea Carrera) in Fulham. This was £70 and they look great, and are matching in colour now (there is an option with Boxster 996 to have them in the body colour i.e. silver).

The final parts for me to source are the discs (which I will order from Chelsea Carrera) 84 - 89 non-S disks. Then the adaptors kit for the front from Transporterhaus.

 

[naskeet]

Bear in mind, that the ratio of front to rear braking torque, should remain virtually identical to that of the VW Type 2 factory-standard system, otherwise you could experience wierd oversteer or understeer effects, under braking! :roll: :shock:

 

[adamski]

Good to bear in mind in terms of the set-up. The garage I use have experience of porsche brakes on a bay so I'll make sure I ask (Autotechniks).

 

[Haveacamper]

I thought about the the whole brake bias between the front and back when I fitted the discs on the rear of my bus. Is there any adjustment in the bias valve. I don't remember seeing anything that allowed u to change

Maybe if u the balance is out u could get an adjustable bias valve

Thinking about it would having a bad balance be an mot failure? I've got discs front and rear and passed

EDIT. What are u doing for ur handbrake if you are going for Porsche rear brakes???

 

[adamski]

Good question....hmmm hand brake. I'll need to ask the experts!

 

[aogrady]

I thought about the the whole brake bias between the front and back when I fitted the discs on the rear of my bus. Is there any adjustment in the bias valve. I don't remember seeing anything that allowed u to change

Maybe if u the balance is out u could get an adjustable bias valve

Thinking about it would having a bad balance be an mot failure? I've got discs front and rear and passed

EDIT. What are u doing for ur handbrake if you are going for Porsche rear brakes???

Could you not fit a brake bias valve, the sort of thing you see on motorsport applications?

http://www.a1performanceproducts.com/bias-adjusters/brake-bias-adjuster.html" onclick="window.open(this.href);return false;

http://www.compbrake.co.uk/BRAKE%20ACCESSORIES/BRAKEACCESS_BIASVALVE.html" onclick="window.open(this.href);return false;

You can then adjust the balence to whatever you need.

I'm sure not having a handbrake is a mot fail too.

BTW, still not had time to fit my air shocks, what have you decided to use?

Cheers,

Alistair

 

[lhu128l]

i don`t think its the bias valve but the master cylinder you change .a 944 has different size pistons front to back than a drum brake van , usually you just fit the 944 ms

 

[naskeet]

i don`t think its the bias valve but the master cylinder you change .a 944 has different size pistons front to back than a drum brake van , usually you just fit the 944 ms

The Porsche 944 master cylinder, is designed for the Porsche 944 front / rear weight distrubution!

Master-cylinder bores & brake-cylinder and/or brake-caliper bores, are sized according to the normal front to rear weight distribution and appropriate front & rear braking torque. The bias valve, simply limits the rear braking torque, to avoid rear-wheel lock-up, under heavy braking, as a result of "weight" transfer to the front wheels, as the vehicle "nose-dives".

 

[adamski]

I've decided to go for the KnK kit. I collect it next week when I'm in Holland for work.

I'll give Alex from Transporterhaus a call tomorrow about handbrake. I had heard about fitting a value to sort the brake balance, but will do some more research

 

[adamski]

The hand brake will work as part of the rear kit that Transporterhaus are developing. It will be 944 based.

 

[adamski]

i don`t think its the bias valve but the master cylinder you change .a 944 has different size pistons front to back than a drum brake van , usually you just fit the 944 ms

vwjim just raised this with me. Not sure which m/c to use. problem with 944 is that they have the engine in the front so usually bias is out. Maybe I'll use a 944 one. not sure yet.

 

[alex4057]

Your van really is going to be one of the best kitted out EB's in the world, Loving your work Adam :mrgreen:

 

[adamski]

Thanks Alex. Its taking its time at the moment, but slowly does it....I haven't even posted anything about my other project....the interior. I think I will keep that to myself (well just not the www)

 

[adamski]

Front Discs - 84-89 Carrera.

 

[lhu128l]

x drill those babies !!!