Date:         Sun, 7 Nov 2010 07:04:13 -0800
Reply-To:     Don Hanson <dhanson928@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Don Hanson <dhanson928@GMAIL.COM>
Subject:      Was Smartphone....Now: conventional Dyno for tuning?
Content-Type: text/plain; charset=ISO-8859-1

  While I have no experience with Smart phones and their dyno apps,  a
regular dyno is the way to tune, to modify effectively, to quantify actual
gains as you attempt to improve on your vehicles.

 I wish I'd done a baseline dyno run on my recently-revised 1.8 l inline
motor so I could compare what my actual increase in power has been .  Having
actual numbers 'means' something...Seat of the Pants impressions?....not so
much.   A few hours on a Mustang dyno (the one I am familiar with) after
every major modification, tuning and tweeking, then you know you have found
every last hp and lb/ft of torque possible from your latest 'improvement'
 It's quite illuminating.  Surprising, too, how much can be gained or lost.
 Also informative to 'de-bunk'.   A lot of 'common knowledge'  can be shown
as urban myth.  Counter-intuitive changes can sometime give good performance
improvements.  Expensive aftermarket modifications sometimes give no
meaningful gains.  I would love to see some dyno print-outs on all the
various engines used in Vanagons right now...from the same type dyno.  I bet
we would be surprised at some of the numbers.

   The 'work-around' that I use with this Vanagon instead of taking repeated
trips to Portland for actual 'roller-runs' is to repeat runs up a familiar
highway with a long (about 4mi) steady 7% upgrade, see what kind of speeds I
can sustain.  Crude.   It's so much better to have some real print-outs.

  Some folks I know of use a widget called a "G-force". I assume these are
similar to what you might get with a Smart Phone app....GPS, accelerometer,
timing and some algorithms.  These system's number's don't seem to jibe very
meaningfully with the performance of the vehicles they are linked to in all
cases, though I suppose you might get some useful data, percentage-wise..I
would want to do some 'repeatability testing' to see if you could get the
same numbers in repeated 'runs' using an I-Phone..An actual inertial
dyno--that can give us 'apples to apples' numbers without a lot of
variables.

  Don Hanson

On Sat, Nov 6, 2010 at 10:10 PM, David Beierl <dbeierl@attglobal.net> wrote:

> At 12:02 AM 11/7/2010  -0400, Greg Potts wrote:
>
>> For $13 it'd be pretty useful to tell you if that $50 widget actually
>> did make a difference or if it's just a placebo effect...
>>
>
> Are you absolutely sure you want to know? <g>
>
> Yrs,
> David
>