Re: Ring Brakes

[Brett Dikeman <brett@pdikeman.ne.mediaone.net>]

A gross oversimplification.

What they're talking about are the internal caliper brakes on some 
V8's and the 1991 200 Quattro 20v(and only the 20v.)  Some 200q20v's 
were converted with a factory kit, but the V8's were too heavy and 
the conversion would leave the car with not enough braking power. 
Only the front wheels had internal calipers; the rears were just 
plain vented discs.

These brakes use a caliper which sits inside the rotor, instead of on 
the outside like on most cars.

It has one major advantage: the diameter of the rotor can be much 
bigger with the same sized wheel, which yields better braking "power".

It's very hard to explain in words what it looks like, but here's how 
to spot one: basically, if you're looking at a V8 or a 200q20v and 
you see what looks like a heat shield peeking from behind the BBS 
wheels, only it's made of really thick metal...that's part of the 
internal caliper design, and that's what holds the rotor.

The internal caliper design was abandoned by Audi after problems with 
warping; I think, but I'm not sure, that a few other car companies 
experimented with them, but not many in production cars.  Some say 
it's heat, some say it's the shape/nature of the design(in which a 
rotor is, like you say, just a "ring", basically.)  The point 
is...lots of people complained about the rotors warping and causing 
wheel wobble when braking, so Audi replaced some under warrantee. 
They are more expensive than regular rotors by a significant amount, 
so this can cost big $.

However, I have them on my car and they brake like hell, and I don't 
have any problem with warping.  The design provides for some serious 
stopping power that just isn't possible with an outside caliper under 
15 inch wheels.  Yes, they're more expensive for rotors, but for the 
once in a while where I might need to replace them, I can deal with 
that.  Drive like a sport, pay like a sport.

The qualities of the 200q20v far outweigh the problems some people 
have with the front brakes(but I am admittedly biased on the 
subject.)  The 200q20v is still  one of the fastest cars Audi built 
for production; definitely in the top 5.

The internal caliper cars that have been converted are often 
underpowered in terms of braking ability(though this is currently 
being debated on the 200q20v list.)  Some 200q20v owners save up and 
convert to 16 inch wheels from an S car or A8(or aftermarket) and 
install high performance normal caliper brakes(like the famous 
Porsche red's) which are even better.

Someone scanned in a picture of the internal brake assembly from the 
Bently(repair manual set) but I don't recall who has them.  Someone 
will probably respond with the URL. I might be able to take a digital 
pic or two of my car tomorrow if you're really interested.

BTW, these brakes are often called UFO's because they look very much 
like your "average" U.F.O. when off the car.

Brett
91 200q20v(with internal caliper brakes.)

At 9:54 PM -0700 4/17/99, David Glubrecht wrote:
>  A while ago I saw an article bout buying older Audi's and one thing
>it said was to stay away from Ring Brakes, I have no idea what these
>are and am curious, is there any pic's that anybody has put up or
>anything?
>  just curious
>  David Glubrecht
>  Many Audi's never seen ring brakes

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Brett Dikeman
brett@pdikeman.ne.mediaone.net
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