October 2021: Since a few weeks I have been in contact with Pierre Duperrey, and bought his brake disc kit for the Traction Avant 11BN/L.
THE INSTALLATION MANUAL FOR THIS KIT IS AT THE END OF THIS ARTICLE!
Also, Pierre was so kind to guide me to the sellers of the brake calipers, -pads and -discs.
Pierre has developed a system to get disc brakes on your Traction Avant. And the way he made this, it will not be visible on the outside of the car, nor in the motor compartment. Only when you look under the car it becomes apparant that it is not what you would expect to see.
The developed kit is extremely sturdy, and the developed 2-part saddle that is mounted on the inside of the existing mounting sleeve that is in the old situation carrying the brake mounting plate of the drum brake system, is very solid.
From Pierre you can buy a set that fits to your existing stub axle bowl and the brake calipers are attached with a newly made saddle at the points where the brake anchor plate of the drum brakes is now attached.
The main part of the saddle exists out of 3 laser-cut parts that will need to be machined into 1 part, that attaches to the 2nd saddle part to enclose the mounting plate on the axle bowl.
Pierre communicates in French only, and I established a good understanding between us by using Deepl.com to translate French to Dutch and vice versa.
Pierre supplies all the hardware that you can’t actually make yourself, unless you can do the laser cutting of steel and make the necessary adapters for the hub to the discs yourself.
This means that you have to buy the brake discs, calipers and pads yourself anyway. You need to have exactly the right types because otherwise it won’t fit in the narrow available space.
You do have to disassemble your existing brake drums and re-use the inner part ( the hub) that sits on the drive shaft. This is where the brake disc is attached to this reworked part with an adapter ring. The adapter ring is one of the parts Pierre can supply.
Connecting the brakes to the existing brake system requires a new flexible brake line between the metal supply line and the brake calipers on both sides. Pierre also fabricated these lines for me, including the adapter to the calipers.
Because Pierre relies on an external supplier for the specialized laser cutting and machining work and he works to individual orders, it may take a while for everything to become available.
If you add it all up: the brake discs, the brake calipers, brake pads, brake lines, adapters, brake saddles, bolts and nuts it will set you back some 1400 Euros. If you also want to do something to the master cylinder or make diversity brake circuits, it will obviously set you back some more.
This modern installation must be used with a brake fluid that is not aggressive, and the continued use of the original brake fluid is for a number of reasons not recommended. It is better to change everything at once to DOT3 or DOT5. I advise not to use DOT4 because this may cause swelling on specific type of rubbers and it has been proven that DOT3 and DOT5 does not influence any kind of rubbers in the long run.
I am using DOT3 for over 5 years now and I have only positive experiences.
One of the characteristics of DOT3 is that one of the additives in DOT3 is a greasing ingedient that helps the existing steel calipers and pistons not to rust onto each other any more.
Of course, you will still have to do normal maintenance like exchanging the brake fluid every so many years, like with all cars.
There are already some satisfied Traction drivers using these brakes developed by Pierre!
In the accompanying pictures you can see what Pierre can do and how everything is put together:
Actully, I would prefer a caliper saddle that was available in the 1990’s but this does not appear to be available any longer, nowhere. This saddle could be mounted on the outside of the brake mounting plate and was made in 1 piece of machined steel. It looked like this:
Brake mounting plate for the drum brakes removed, left side of the car
TA DISC BRAKES ‘Version Pierre Duperray’ INSTALLATION MANUAL
Mounting the new disc brakes is described below, please also check the published pictures in the top of this article. Using both, it should not be very difficult to perform this job.
I will start my rebuild in May-2022 due to a lot of other work that needs doing at my other car. Since I don’t have space for 2 cars I will first get the existing work done, and that will be May 2022. I hope. -)
Most rebuilds don’t change the master brake cilinder.
It could be a good idea to exchange the master brake cilinder with a dual-output cilinder so you can make 2 seperated brake circuits.
The problem with this is, that the Traction Avant just does not have enough available space for any kind of longer master brake cilinder.
And any cilinder that has more chambers due to more outputs is automatically longer than the existing one, if you require the same throughput (which equals thickness). Although you could do with a bit less travel but the added (or longer dual) piston and seals just amount to a much longer dual output master brake cilinder than a single output type.
I believe that this is the main reason that almost nobody that gets disc brakes on the Traction Avant, puts in a double separated brake system.
But- alternatives could be developed or may aready have been developed.
If anyone has ideas about this, please let me know and I will share this here!
Just mail me at email@example.com