Re: 81 coupe brake upgrades

[Alex Kowalski <akowalsk@shrike.depaul.edu>]

R. Tonge wrote:
> 
> Dear All,
> 
> Just got back from a totally awsome trip to canada (Jasper, Banff, Radium
> Hot Springs etc - 1600 miles in 4 days and totally trouble free - good
> these audi's !!) and experienced brake fade a couple of times on some
> sharp gradients. I was wondering if anyone has upgraded the brakes on the
> coupe from the solid disk setup upfront - I assume there must be a vented
> setup somewhere. Also has anyone put disks on the rear of these - I
> believe some of the 87 coupe's had rear disks ?? will they fit and is it a
> big job ?
> 
> Thanks
> 
> Rob.
> --------------===============<<<<<<<<<<<>>>>>>>>>>>==============-------------
> Robert P. Tonge, PhD           _____    _    ____
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I used to have exactly the same car.  My response to a post similar to yours in in the archives, 
but no bother anyway.

I upgraded the front rotors to the 9.6" cross-drilled and ventilated Brembos (from Rapid Parts, 
advertised in the back of European Car magazine or call information for Tallman, NY).  The front 
calipers are you have are fine, but you will need to find a set of new set of caliper mounting 
brackets (which bolt the calipers to the strut housing) fron a later car with ventilated 9.6" 
rotors, probably an '85 or '86 4000 that has them. If you find the brackets, you don't have to 
disconnect the calipers from the lines unless you want to. I got my brackets from a junk  yard 
and they were in fine shape.  You need them because the slot on your caliper brackets isn't wide 
enough to accomodate the ventilated rotors.  You should be able to get them for ~25$ or less.  
Get a set of new, hardened bolts for the mounting brackets and calipers from your Audi dealer if 
you can, or else carefully inspect the old ones, clean them with a wire brush, and Loctite them 
in place when you reinstall them.  If there are any marginal threads at all, replace them.  Those 
rotors, in combination with Repco Metalmaster pads, made a gigantic difference in the stopping 
ability of my car.  While you're at it, replace the rear drum shoes and check the drums 
themselves.  RP should have shoes for the car.  It is a little more involved, but worth it.

Finally, if you want maximum feel, get a set of stainless steel braided lines for the brakes from 
them.  This will require you to disconnect the front calipers from the lines and bleed them, 
which is a good idea anyway.

Bleed the brakes completly, flushing all of the old brake fluid out of the lines and replace with 
a nice DOT 4 fluid like Castrol LMA.  Once you have the parts, it's a 4-6 hour job to do all four 
wheels, including purging/bleeding.  Be careful loosening the bleeder screws, get a bleeder-screw 
wrench if you don't already have one!  The front rotors and pads make a big difference by 
themselves.  You shouldn't need to worry about rear discs for that car unless you are running a 
much faster engine than anyone would expect...that car is light in the back as it is.  Believe 
me, the first time you stop hard with the new brakes after you've bed them in will tell you 
something!  You should be able to get the whole thing done, DIY, for under $350. If you have any 
other questions, contact me at:

akowalsk@shrike.depaul.edu


Best of luck
Alex