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Re: Even more Quattro quirks and speedo stuff

We had an impossible time aligning+balancing my 5kCST, mostly because it
hadn't been done in quite some time.

Have the tires aligned+balanced _on_ the car.  The shop we were going to
did this after they went out for a ride and we pointed out the problem.
Car now drives like a dream on the highway.

>even speak those words!  Anyway, I've been getting this strange steering
>wheel shake under throttle/torque.  It just started happening recently and
>it occurs at various speeds and conditions, without any consistency.
>Usually above 65 mph.  Sometimes it doesn't happen at all.  When this
>occurs, the dash and center console shake and I can feel it in the gas
>    I had the front end checked out by a very knowledgeable Audi mechanic
>and he said everything up front is tight.  So I thought- trans mounts.
>Nope, was just told these are solid, no play what so ever and the engine
>mounts are also good.  I even had the tires balanced just to be sure.  They
>were right on.  I can't figure this one out.  Any suggestions would be
>greatly appreciated.
>    A note on gearing since this seems to be the hot topic of the week:  my
>854ksQ runs at about 65 mph just under 3000 rpm and 80 mph at about 4000
>rpm.  Just for comparison.

I'm building a chart of data using my new GPS unit(recommendations on the
Garmin GPS II+ are all good...it works even on the front seat instead of
the dash.)
I'll run it through the 'ol freeware data graphing program and then through
the freeware data-fit program; I'll post data from others, but be forwarned
that I don't want the data unless it came from a GPS unit(no radar guns
either...how could you possibly rely on someone outside the car reading at
the same time?)  No "my friend was driving next to me in my XYZ Zipster
which has a dead-on speedo and he signalled me that his speedo read..." :)

As a general rule of thumb though, I've found my speedo to read around 10%
high.  45=40mph, 80 is really 72, etc.

Remember, it is important to get a variety of speed readings for true speed
vs. indicated; it's not necessarily linear!
RPMs vs. speed included, because the speedo could have a non-linear error!

I will suspect that the majority of differences in speed vs. rpm will be
accounted to different stages of tire wear.

BTW, I checked on the accuracy of my GPS unit; .1 knots RMS.  That means
.11 mph.


Brett Dikeman
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