Re: 5k RPM's at 65mph

[Brett Dikeman <brett@arthur.malebolge.com>]

I've tried to match my speedo, odometer & highway mile markers. There are
no constants so I gave up. I hope I don't get tickets for it.

I found an excellent way to do speed measurements, and it is extremely
accurate and constant(down to .1mph or so.)  GPS.
With a co-pilot(aka navigator) we played with a tripmate and pitted the
Volvo wagon's speedo against the GPS unit.  At all times, they agreed
perfectly(to the best of my reading abilities.)

And no, selective availability does not affect speed measurements; the
distance covered at 70mph is 102.6ft; averaged over 5 seconds that's 500ft
or so; plus, selective availability isn't "fast"; changes are gradual(maybe
10ft in a second or less)...So, because your absolute position doesn't
matter, rather your relative, speed calculations with GPS units at highway
speeds are very accurate.

Anyone who joins the caravan to Pike's Peak from the NE area is welcome to
a free speedo evaluation(providing everyone has CB's.)  Might even
volunteer to do it at Pike's Peak.  Sounds like a "real" excuse to go to
Pike's Peak to me :)
S.O.:Why are you going to Pike's Peak?
A.F.:Uhhhh...to get my speedometer adjusted?


(Sig. Other., Audi Fanatic.)

>To maybe add something here and I don't know how significant this is to
>the general >Audi public but both of my '87 5kcst's odometers show approx.
>10 miles higher than >the actual speed.  I measured them against my
>Lincoln TC which has a digital dash >which I have again measured against a
>police radar and is correct.  Both cars have >the 15 inch turbo alloys. 
>Why this is I do not have a clue, but maybe this problem >is more
>widespread.

3000 rpm "reads" to be 80mph or so on my 5kcst.  It's really closer to
70mph.  When I pick up a new gps unit and find someone to help run it, I'll
report back.

Personally, I think it's a conspiracy :)

Dare I suggest this is why we all think our cars handle so great at speed,
because our speedos all read high?  Yikes!  No flames please, I wasn't that
serious(though it makes you wonder!)

> >Depends on the 5k.  My 5k definitely does _not_ do 80mph at 3000rpm.
> >Closer to 65mph, and 4000rpm at 80mph, similar to your figures for the 4k.
> >My 5k (an '87 S model quattro) has the lower gear ratios.  I don't know
> >personally what determined which gear ratios were used in which 5ks.

I thought that all the manual gearboxes(excepting FWD vs. AWD) in the 5k
were the same?  Seems to be a popular transmission; some Porsche 944's
sport the 5k's transmission backwards, hanging over the rear wheels.  I
assume it was not an Audi design(do I recall hearing it was outsourced to
some company?)


Brett

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Brett Dikeman
brett@pdikeman.ne.mediaone.net
~)-|
Hostes alienigeni me abduxerunt.  Qui annus est?
Te audire non possum.  Musa sapientum fixa est in aure.
Ita, scio hunc 'sig file' veterem fieri.
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