RE: [s-cars] RE: BIRA vs Big Red (ECS2, etc)

[TM]

Hap-
What I really meant about the rear brakes was that I have not seen any
research that has shown definitively that increasing the rear braking
power
significantly improves braking distances. As a matter of fact, most
articles
on braking performance warn about over-biasing toward the rear, as this
can make the car extremely twitchy and prone to rear-wheel lockup, thus
increasing braking distances.
 
I can see how your suspension modifications may change this aspect of
weight distribution under braking, but I don't understand how your brake
modification in the rear would significantly improve braking distances.
Have
you gone out and tested your modification, before and after, to see
what, if
any, changes have occurred?
 
The Porsche cars that have relatively large brakes do so primarily
because of
the rear-engined nature of the cars causing a significant amount of the
cars'
weight over the rear axles, making rear brakes a lot more important than
in
our Audis.
 
If you look at some of the really high performance front-engined
vehicles out
there, even those with nearly perfect 50/50 weight ratios, very very few
of those
vehicles have really large rear brakes. It's way overkill, even on a WRX
STi or
an Evo8. The only cars I've seen that has huge rear brakes from the
factory is
the Volvo S60/V70R, the Audi RS6, the Maybachs and the S55/S600/S65
series
of MBZs. Of those, I only have personal experience with the Volvo, which
I really
don't understand why they put such huge rear brakes on the car- they
don't seem
to make the car brake any better.
 
To do a side-by-side comparison that is scientific, you would have to
run identical
suspension setups, tires, wheels and ballast the cars to the same weight
on the
same track at nearly the same time. Otherwise, there are far too many
variables at
play to make any meaningful conclusions.
 
Taka

-----Original Message-----
From: CaptMagu at aol.com [mailto:CaptMagu at aol.com] 
Sent: Tuesday, August 03, 2004 12:38 PM
To: t44tq at mindspring.com; WQQ2PXK at ups.com; s-car-list at audifans.com
Subject: Re: [s-cars] RE:  BIRA vs Big Red (ECS2, etc)


Taka

I think you're a little off base here Taka. Its always a combination of
things as in the entire setup that usually brings a solution to a
challenge. In Robert's case and mine to a lesser degree, His full hard
setting on the rear shock rebound as well as his front compression on
shocks plus the 400lb front springs all combine to dampen the front
dive. Yes, the springs and shocks should be tuned in tandem. When I
talked to Bilstein prior to the revalve, they were very keen not to over
dampen with the shocks but in concert with the springs. They asked for
all the info I had including corner weights, spring rates and sway bar
rates.

As far as the BRBU(Big Rear Brake Upgrade) goes, I had minimal dive
before the shock revalve. Everyone that has driven the car has commented
on the lack of dive. It would be cool to do some side by side braking
with Mr Caro. I don't do the mods on my car strictly looking at price.
I'm looking at the total package. A lot of us have too much invested in
these cars but its what we like to do. 

Hap, talkin dahkine breaks in Evahboost, Maguire