Date:         Sun, 13 Sep 2009 09:59:21 -0700
Reply-To:     Roland <syncronicity1@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Roland <syncronicity1@GMAIL.COM>
Subject:      Re: Wheel alternatives...
In-Reply-To:  <11564931.32654.1252852716942.JavaMail.mcneely4@127.0.0.1>
Content-Type: text/plain; charset=ISO-8859-1

Dave,

A vehicle like the Vanagon is not created by just engineers; designers and
accountants have as much say as the engineers.  And so the result is never
an optimal engineering result.  The goal of engineering work varies
depending on the application.  On a car like the Vanagon the engineering has
to be "good enough"; it is not worth the extra money to make a Vanagon a
highly excellent engineering result, since it would cost too much and buyers
don't really want  the more highly engineered product.  They like a lesser
car at a far lesser price.  On the space shuttle the engineering has to be
near perfect.  But even within the engineering decisions, there are always
tolerances.  Some tolerances are very tight, and others are very broad.
With a broad tolerance there is room to make changes without compromising
the function of the part of the design characteristics of the assembly.
So... we can't make an assumption that a car is optimally engineered.

People upgrade to 15 inch wheels for a variety of benefits including more
tire choices, a more stable ride, and sometimes for better looks (we are
allowed to be designers and accountants as well as engineers as we plan to
improve our Vanagons).  Some Syncros are upgraded to steel wheels for more
reliable offroad performance.  Some street Vanagons are lowered with
corresponding wheel changes to accommodate much lower profile tires and
therefore better cornering performance (larger wheel, shorter sidewall).

However, I am like you with concern that removing material from the lug
holes would result in a wheel that is safe enough.  Maybe if we were sure
that the alloy in the Mercedes wheel is of a higher quality, then that would
give some confidence.  But a higher confidence would be created by doing a
structural analysis of the resulting wheel, since things like stress should
be analyzed.  The design of the part is as important as the material for
structural integrity.  In this case as David wrote he had to trade off fewer
turns of the lug nut vs removing material from the wheel.  It would be best
to do the structural analysis to see which change would cause less a less
weak result.  But most of us don't have these skills, maybe gut feel is all
we can do.

Roland

On Sun, Sep 13, 2009 at 7:38 AM, Dave Mcneely <mcneely4@cox.net> wrote:

> I am forever amazed at the propensity of folks to change something on a
> vehicle from the way the engineers designed it, and dismiss any concerns
> about safety of the modification with faith that it will "be ok."
>
> Why do you guys want different wheels from the ones that VW put on the
> van?  In what way do you think that your choices are better?  Just
> curious.
>
> Dave McNeely
>
>
> On Sun, Sep 13, 2009 at 9:18 AM , David Vickery wrote:
>
>  Well, they didn't get stronger by removing about a half inch out of
>> each hole I can tell you that.  OTOH, I removed enough material to get
>> the same # of turns before the OEM alloy wheel lugs seat.  I think
>> that was about 7.5 turns.
>>
>> Everything about the MB wheels seems better quality, so I am assuming
>> the alloy is as strong or better.   If VW concluded it was safe to
>> machine the wheels to be that thin on the van, I expect the MB wheels
>> will also be o.k.
>>
>> Dave
>>
>>
>> --- On Sat, 9/12/09, Bob Stevens  wrote:
>>
>>  From: Bob Stevens Subject: Re: Wheel alternatives...
>>> To: "David Vickery" Cc: vanagon@gerry.vanagon.com
>>> Date: Saturday, September 12, 2009, 11:19 PM
>>> Dave,Any idea, based on the amount of
>>> material you had to eliminate from the bolt holes, what that
>>> may have done to the OE intended load-bearing capacity of
>>> these wheels?Just curious.bob
>>>
>>>
>>> On Sat, Sep 12, 2009 at 10:44 PM,
>>> David Vickery wrote:
>>>
>>> I finally got around to fitting MB wheels on my syncro.  I
>>> used the OEM MB 8 hole, 15x 6.5 or 7, ET 37 from a 90's
>>> C class car.  I finally got them to be direct bolt on to my
>>> or any van.  The hubs are the right size but the thickness
>>> of the alloy required a lot of machining to get them to
>>> direct bolt on.  I learned a lot in the process and had
>>> checked into wheel adapters and longer studs before deciding
>>> to ream out the holes to the same thickness as the OEM VW
>>> alloy wheel.
>>>
>>>
>>>
>>>
>>> Initially I thought it would be more expensive to get wheel
>>> adapters, so I went with wheels that had about the right ET
>>> 37 vs. stock 30.  I wouldn't do it that way again.
>>>
>>>
>>>
>>> I also had bought the longer studs that were intended for a
>>> 911 and I bought longer lugs too when I had a 2wd van.
>>>  That was expensive too and was more involved that I wanted
>>> to get into so I resold them.  Plus they aren't really
>>> bolt on when you do that, they only bolt on to a modified
>>> van.  I wouldn't do it that way again either.
>>>
>>>
>>>
>>>
>>> If I had to do it over again, I would find wheels with a
>>> large offset like ET60 and I would just buy adapters to bolt
>>> on before bolting on the wheels.  That would be the easiest
>>> way to go, and in the end the cheapest if you figure in any
>>> cost for your time and tools or other parts you will have to
>>> buy.  The drill bits to ream out the holes cost almost $100
>>> by themselves.  Plus someone mis-informed me and I had to
>>> buy a second countersink bit.
>>>
>>>
>>>
>>>
>>> You can adapt the larger ET wheels easily and the bolt
>>> pattern options are plentiful from places that sell
>>> adapters.  You can also get a 25mm thick 5/112 to 5/112
>>> "adapter" that just corrects the offset and is a
>>> direct bolt on with MB wheels.  The link below is
>>> $52/adapter but I think I saw them a little cheaper
>>> somewhere else.
>>>
>>>
>>>
>>>
>>> http://adaptitusa.com/index.asp?PageAction=VIEWPROD&ProdID=165
>>>
>>>
>>>
>>> Sounds like the link posted from thesamba has all the
>>> correct info.  But this was my experience after going
>>> through it.  And I didn't know about the samba link
>>> when I started.
>>>
>>>
>>>
>>> BTW, I did all the machining by hand drill, and it worked
>>> out fine.  I later found a wheel shop in Denver that
>>> machines them for $20/wheel.  Oh well.
>>>
>>>
>>>
>>> Dave in Denver
>>>
>>>
>>>
>>>
>>>