Front Disc brakes for your Traction Avant 11


After converting my Traction Avant to 4-speed, I noticed that the car’s braking power is only just sufficient to drive safely in today’s traffic. 

Unless you firmly press the brake pedal; then something does happen!

Especially with several passengers in the car the braking power seems to be on the small side, probably because we are used to power brakes in modern(er) cars.

Kicking harder on the brake pedal also helps, and the well adjusted new brake linings on the brake drums make sure that the car will block on all wheels in case of a panic stop.

Nevertheless, I started looking for possibilities to mount disc brakes on the front wheels.

In France, until 2004, there was a manufacturer that sold kits with discs, caliper adapters and calipers. 

Without a brake booster but that is certainly not a big problem, a 7 inch brake assist booster (aftermarket add-on)  fits from any ’60-’65 kit . So this might be the next project:

Did call and email but never got in touch….

Still going to make it myself! 

Or just place a brake booster in combination with a suitable master cylinder, then I can use the existing drum brakes and make 2 separate circuits.



NEW!!!  2020: Now available in France:

Add Front Disc Brakes to Your Traction Avant


Add Front Disc Brakes to Your Traction Avant

Pierre Duperray in France will soon be offering a front disc brake conversion for the Traction Avant.

You may remember him as we have covered in the past his creating 4 speed gearboxes for both 4 cyl and 6 cyl Tractions.

He is currently preparing to fit disc brakes for on his Traction 11BL.

Pierre says that the assembly is very easy to install. And the cost?

  • Brake calipers and pads = 500€ (2 sets) — manufactured by Wilwood.
  • 2 Discs = 150€ (Audi)
  • Flexible Brake Hoses = 80€
  • Machining = 300€ (part with first laser cut)

Total: about 1,000€

Pierre thinks that this solution is also possible for the 15-6, though it will be necessary to modify the hub.

And the pictures of Pierre’s conversion to disc brakes:

Another anonomous conversion off the onternet:

What do you need to convert your front brake system from drums to disc brakes?  That depends a bit on:

Do you want to leave the original operation with the single master cylinder or do you want to build something else in? 

To make it work properly you will probably need to add a brake booster.  Or maybe not if you use the 4-piston brake calipers. And- an add-on brake assist will be very visible under the hood ….  Obviously it is not possible to mount a normal type of brake booster that mounts between the pedal and the master cylinder in a Traction Avant.

Should I choose to convert to disc brakes, I would choose to mount a new master cylinder with cross switched  similtauous  brake circuits, for safety.  And possobly a brake booster, if needed. 

The pistons of the disc brakes have to give more pressure to brake at the front because they also brake a smaller area than with the drum brakes and at the front you need more braking power than at the rear on the drum brakes.

I found the following parts on the internet, noting that the best solution seems to be a 300mm disc, with a quad-piston caliper and a caliper bracket with a difference of about 3 inches, namely towards the side of the bike.

Provided you mount it correctly, of course. 

I deliberately don’t choose a caliper with a brake saddle and piston on 1 side.  I try to stay as close as possible to the positively proven after market kit as shown in the photos at the top of this article.


error: Content is protected !!