Date:         Fri, 3 Feb 2012 14:00:11 -0800
Reply-To:     Zeitgeist <gruengeist@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Zeitgeist <gruengeist@GMAIL.COM>
Subject:      Re: Jaguar vs. Passat brakes on Vanagon
In-Reply-To:  <77F22EDD-F767-449D-BE5C-0F29DEED92C7@gmail.com>
Content-Type: text/plain; charset=UTF-8

Yeah, I think some folks are over-thinking this a bit.  My Mercedes uses a
similar two piece hub/rotor and has an even thinner mounting surface and
lug hole material, yet the car weighs roughly the same as the van.  This is
a very common design on today's vehicles, and I assume the T4 uses
something quite similar.  I have seen some folks machine their hubs down
much closer to the lug holes than I'm comfortable with, but so far there's
been no indication of failures due to this setup.  If you've ever done the
brakes on this arrangement, you should appreciate the fact that you don't
need to mess with the wheel bearings when R&Ring the rotors.  I loathed my
stock Van brakes due to fade issues.  The stock rotors weren't warped, but
they were both a uniform dark blue color, indicating that they'd been
subjected to quite a bit of heat.  The larger T4 rotors I swapped in there
are vented, and should do a much better job of avoiding heat-soak.

On Fri, Feb 3, 2012 at 1:02 PM, Chris S. <szpejankowski@gmail.com> wrote:

> So your concern are the threads going into the machined hub.
>
> Newer VW vehicles use front hubs and hub-centric rotors which do not
> utilize press-in studs. The pressure of lug bolts holds the wheel and
> rotors in place. Perhaps the hub material in those hubs are of different
> hardness to handle the extra load. It would seem that the forces would be
> transferred by the hub face and not the lug bolts themselves. The lug bolts
> merely provide the clamping force.
>
> Chris.
>
> Wysłane z iPhone'a
>
> Dnia Feb 3, 2012 o godz. 6:43 Dennis Haynes <d23haynes57@HOTMAIL.COM>
> napisał(a):
>
> > What you really want to know is the total surface area of the piston(S)
> > combination. This is calculated by the radius squared x pi. A 3" piston
> has
> > an area of 28.274 cu in. Two 1.5" piston have a total of only 14.137 cu
> in.
> >
> > With the original rotors being cast the wheel flange gets much of its
> > strength from the complete rotor piece. There is no way I would rely on
> the
> > wheel flange part to mount the tire with the rotor disk and hat cut off
> and
> > flange cut down to fit inside a different rotor. The threads alone are an
> > issue as the rotors have a defined lifespan and each time a wheel is
> mounted
> > there is some wear and distorting of these threads. Have a machine shop
> make
> > a hub from solid steel and use pressed in studs instead of lug bolts.
> This
> > will also allow the flange to be placed for proper disk alignment or
> wheel
> > spacing.
> >
> > I would also consider that a major change to the front brakes should also
> > include a matching change to the rears. The rears contribute a lot more
> to
> > stopping than many would think. A properly working rear set up has a lot
> of
> > surface area. A real problem with the rears is that the aftermarket
> shoes do
> > not have thick enough linings and without some compensation only part of
> the
> > shoes contact the drums. I have posted a number times shimming the lower
> > shoe rests out the get more of the shoe to contact the drums. Also the
> rear
> > brake pressure valve can fail causing poor rear brake action. With good
> pads
> > up front and the rears working properly the stock brakes can work quite
> well
> > until you go to larger tires.
> >
> > Dennis
> >
> > -----Original Message-----
> > From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
> Of
> > ralph meyermann
> > Sent: Thursday, February 02, 2012 8:58 PM
> > To: vanagon@GERRY.VANAGON.COM
> > Subject: Re: Jaguar vs Passat brakes on Vanagon
> >
> > Whats the total of piston diameters?
> >
> > Velma 82diesel 1.6 na westy
> >
> > On Feb 2, 2012 7:54 PM, "BenT Syncro" <syncro@gmail.com> wrote:
> >
> > Chris,
> >
> > At quick glance, the biggest difference is twin piston calipers for the
> Jag
> > and single for the Passat's.
> >
> >
> > BenT
> >
> > sent from my electronic leash
> >
> >
> > On Feb 2, 2012, at 4:45 PM, "Chris S." <szpejankowski@GMAIL.COM> wrote:
> >
> >> What's the list opinion ...
>



-- 
Casey