Need coupe GT information.....lots..lol

[Jonathan Monetti]

I've never seen the braking distance figures for an 87.5 ('86 -- 179 ft from
70MPH), so my $.02 is seat of pants.  But logic and physics says that the
larger swept area added by rear discs will provide greater transfer of
energy, thus shorter stopping distances.  I guess the question you pose
is...'Just how much, really?'  I suppose the only way to know for sure would
be to do a side by side test or dig up old MT and C/D road tests for the '86
& '87.5.

I noticed the prop valve on my '87.5 is of a different (and apparently
improved) design from my '86, and did wonder how much that was helping the
straight-line control.

Jason, if you do the conversion, do some before & after 80-0 and 60-0 tests,
will you?  ;)







> -----Original Message-----
> From: Ti Kan [mailto:ti at amb.org]
> Sent: Wednesday, November 24, 2004 8:11 PM
> To: Jonathan Monetti
> Cc: killerb09 at hotmail.com; quattro at audifans.com
> Subject: Re: Need coupe GT information.....lots..lol
>
>
> Jonathan Monetti writes:
> > > Since the front brakes do most of the work of braking, switching to
> > > rear discs won't really yield that much improvement.  In fact, you'll
> >
> > Ti, I have to disagree...
> >
> > The stopping power and pedal feel on my '87.5 with four wheel
> discs is far
> > better than the (same front) disc, drum setup my '86 has (or had...I've
> > cannibalized her so many times).  The '87.5 brakes with a lot
> of authority
> > and no scary drama, whereas my '86 felt a lot like my old Scirocco--the
> > fronts and the rears heated/faded/cooled at different rates, wore
> > differently, and didn't inspire straight-line confidence. (i.e., during
> > really hard stops I thought I'd sometimes end up in a ditch).
> >
> > Jason, I have factory rear-discs, so my $.02 on a conversion may only be
> > worth $.01, but a number of people have given the procedure
> high marks for
> > performance and cost-effectiveness.  It's worth investigation at least.
>
> I'd be the last person to say no to a rear disc conversion since I have
> also done it on my 4000, but that was done in conjunction with a front
> brake upgrade too, so the overall balance wasn't too far off.
> Despite that,
> I still had to re-adjust the brake proportioning valve.  The fact remains
> that the fronts do most of the work.  Brake fade on the drums is
> one thing,
> and pedal feel is another; but in terms of sheer stopping distance, a
> mere change from drums to discs on the rear is not going to get you much.
>
> -Ti
> --
> Ti Kan
> http://www.amb.org/ti
> Vorsprung durch Technik
>
>