<VV> Disk Brake for LM/Now Disc vs Drum

[hallgrenn at aol.com]

Mel,

I agree with everyone on this--now that the debate is between discs and drums.  But, based on Uli's first question I agree with Dan and others that the LM drum brakes--especially with metallic linings--are excellent brakes.  My stock LMs always out-stopped other cars on the highway (to include German autobahns for two of them).  In panic stops from speeds of up to 90mph I never had a problem with fade--I wouldn't try it twice in a row however.  I added Velvetouch metallic linings and (once seated) they were even better and no fade.  (For those of you in Western Maryland a trip down Harp Hill Road without fade is as good a test for brakes as any).

Yes discs are better than drums for many reasons, but I question the logic of putting discs on the front of a LM when the original brakes with metallic linings are so good.  The rears do more of the braking anyway.  If the original front drum brakes aren't up to snuff then pulling might be a problem that discs are less likely to have, but none of us drives with less than perfect brakes do we?

If you are switching to discs and only want to do one end then the rear is the place to start (even if it is more expensive).  But then I'd do both front and rear.

Bob 
CORSA
Group Corvair
Corvanatics


-----Original Message-----
From: Mel Francis <mfrancis at wi.rr.com>
To: Danny Davis <dannydavis at clearwire.net>
Cc: virtualvairs <virtualvairs at corvair.org>
Sent: Thu, Nov 21, 2013 1:46 pm
Subject: Re: <VV> Disk Brake for LM


Right, they were used on the smaller Nova model too. 2" rears on front and 
2.5" fronts on the rear of the Corvair.

Even though Don Yenko used heavily modified drums, if discs had been as 
available then as they are now, he would certainly have specified discs for 
the Yenko Stingers. The one item that makes discs superior is that they 
don't fade to an out-of-round condition on successive hard/hot braking 
cycles.

Car reviews of the period always complained of how American drum brakes were 
only good for one or two hard stops, with 'brake fade' and then wouldn't 
stop the car well at all...

Mel Francis
Oconomowoc, WI

----- Original Message ----- 
From: "Danny Davis" <dannydavis at clearwire.net>
To: "J. R. Read" <hmlinc at sbcglobal.net>
Cc: <virtualvairs at corvair.org>
Sent: Thursday, November 21, 2013 12:28 PM
Subject: Re: <VV> Disk Brake for LM


> Just to keep the facts straight - the Corvair drum brakes are sourced from
> the same bin as the *Chevelle* , not the standard full size Chevrolet
>
> Because of the rear engine and the increased surface area the Late Model
> Corvair brakes were exceptional.  If completely up to specifications, they
> will haul you down nicely - remember that the Yenko Stingers won the
> Championship using the stock drum brakes with the addition of metallic
> linings and vents in the backing plate.  They also had the Cadillac dual
> circuit master cylinder - a worthwhile upgrade for any LM Corvair...
>
> Dan
>
>
>