Date: Sat, 4 Feb 2012 13:50:55 -0700
Reply-To: OlRivrRat <OlRivrRat@COMCAST.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: OlRivrRat <OlRivrRat@COMCAST.NET>
Subject: Re: Jaguar vs. Passat brakes on Vanagon
In-Reply-To: <BAY152-ds13727D7048175BD4864AEAA0760@phx.gbl>
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Dennis
You also came up with "cu in." when it should have been "sq in"
ORR ~ DeanB
On 3 Feb , 2012, at 8:11 PM, Dennis Haynes wrote:
> My concern is both the threads and the face of the hub cracking from
> the center. Yes most front drive vehicles use a flange hub with the
> rotors slipped on or over and many use bolts threaded into those
> hubs but those hubs-flanges are from a solid machined piece of
> steel, not a casting. The rotor casting is designed to work as is.
> That hat and disc adds strength to the flange. Did anyone notice my
> error in the area calculations? I used the diameter, not the radius.
>
> Dennis
>
> -----Original Message-----
> From: Chris S. [mailto:szpejankowski@gmail.com]
> Sent: Friday, February 03, 2012 4:03 PM
> To: Dennis Haynes
> Cc: vanagon@GERRY.VANAGON.COM
> Subject: Re: Jaguar vs. Passat brakes on Vanagon
>
> 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 ...