Jump to content

Welcome to the brand new 205GTIDrivers.com website! We hope you'll enjoy it! Read the full notice here.

  • Welcome to 205GTIDrivers.com!

    Hello dear visitor! Feel free to browse but we invite you to register completely free of charge in order to enjoy the full functionality of the website.

Kobayashi

1.6 rear Drum to Disc Brakes - Question on Pressure

Recommended Posts

Kobayashi

Hi, I am aware that there is an excellent pinned thread on brake upgrades here, but the discussion seems quite dead there.

So:
I will be upgrading my rear brakes from a 205 1.6 GTI drum setup to rear 306 calipers with 247mm discs (should be quite the same as 205 1.9 GTI).
As most of you will know, the stock 1.6 braking system features just one brake line to the rears, and a 1.6-specific pressure compensator.
My plan is to keep that single brake line, BUT ditch the 1.6 compensator and use a Wilwood adjustable proportioning valve instead.

Front brakes will be upgraded to 266mm discs (using 206 calipers on 205 1.9 hubs, et cetera). This combination upgrade has already been done many times, but I am only aware of 1.9 cars which, as said, have a different brake line and compensator setup.

-> Question is, will the rear calipers receive enough pressure in this setup?

Thanks for any good advice. Maybe someone here has already done something similar?

Share this post


Link to post
Share on other sites
petert

Yes, it will work fine. I ran the same setup on my previous race car for many years. If anything, they receive too much and you’ll find you have the new valve just cracked open, effectively giving 99% front and 1% rear. If you want more control, add a second course/fine valve in series. 

  • Thanks 1

Share this post


Link to post
Share on other sites
Thijs_Rallye

The original compensator is regulated on the assembly angle & vehicle angle. I'd try that first. If you change the angle you'll change the pressure as well if my memory serves me right.

Share this post


Link to post
Share on other sites
Kobayashi

I see, thanks. The willwood lever type valve should be the same as the wilwood knob type valve I already have, apart from the lever vs. knob mechanism. Data and technical description are the same.

@Thijs, I did not know that, thanks. Might have a look at it, too.

Share this post


Link to post
Share on other sites
Thijs_Rallye

I used to have a section view of such a compensator but it has been years since I've seen it last. Here is a (short) description of how it works: http://www.peugeot205.ru/peugeot205-205.html

 

There is a ball (comparable to a bearing ball) that has to "roll up a hill" and then shuts a valve which limits the pressure to the rear. So if you change the assembly angle of this valve you'll change the gradient of the "hill" and therefore the pressure limit. Grussli!

  • Thanks 1

Share this post


Link to post
Share on other sites
petert
16 hours ago, Kobayashi said:

I see, thanks. The willwood lever type valve should be the same as the wilwood knob type valve I already have, apart from the lever vs. knob mechanism. Data and technical description are the same.

You may have missed my point. The knob type is infinitely variable. The lever type has six positions. If you only have the knob type, you'll be right at the limit. ie half a turn is enough to lock up the rear brakes. Thus it's beneficial to add a lever type in series with the knob type, then you'll get more control. ie you need BOTH.

 

As said though, it's worth experimenting with the standard compensator first.

  • Thanks 1

Share this post


Link to post
Share on other sites
Kobayashi

Ok now I got you (both of you) - thanks!

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×