> Chris wrote: "Note that all are approximations."
> --------------------------------
> Stan replys: Then why bother?

Chris counter-replies:  Because approximations are the best you can ever
hope to have, even in the engineering world, until you actually build a
prototype and test it.  It's good for A-to-B comparisons and prediction of
trends, if not exact numbers.  For example, it shows how changing your tire
size will affect your accelerations, though not at the *exact* number of
g's.  It will show you graphically how hugely a 240-hp Vanagon would stomp a
1.9 WBX like mine, and so on.  Most of the world's creations were simulated
using approximations first.  : )  Basically if you're thinking about
spending a lot of money on some sort of engine, this can help show you how
much bang you'd get for your buck.

Chris

----- Original Message -----
From: "Stan Wilder" <wilden1@juno.com>
To: <ctb1@PEOPLEPC.COM>
Cc: <vanagon@GERRY.VANAGON.COM>
Sent: Monday, July 15, 2002 7:26 PM
Subject: Re: tiico's, subies and diesels oh my...

> Chris wrote: "Note that all are approximations."
> --------------------------------
> Stan replys: Then why bother?
>
> Stan Wilder
>
> On Mon, 15 Jul 2002 18:55:13 -0400 Christopher Berchin
> <ctb1@PEOPLEPC.COM> writes:
> > << I'm just curious if there is a definitive place to look for
> > comparisons on these engine conversions? >>
> >
> > I wouldn't call it "definitive," but I'm currently working on
> > finishing a
> > spreadsheet with graphical analysis of the 2.2 Subie, 3.3 Subie, 1.9
> > and 2.1
> > WBX engines.  Basically I've plotted the thrust curves for each
> > engine in
> > each gear over the entire rev range.  What I'm working on now is
> > adding the
> > effects of powertrain losses (i.e. frictional losses that are
> > internal) and
> > aero drag.  I have it figured out, I just haven't finished it yet.
> > Once
> > done, I can post the graphs - right now, the only thing that really
> > "has it
> > all" is my comparison of the 2.1 WBX to the Subaru 2.2, but only for
> > top
> > gear.  I have drag and powertrain loss effects only for fourth gear
> > for
> > those engines - what's left to do is to do the rest of the gears
> > and
> > engines.
> >
> > The whole thing is an Excel spreadsheet, so you can play with tire
> > sizes,
> > gear ratios, and dyno cuves to see what happens.  Note that all are
> > approximations, but so far my 1.9 WBX chart says that I should top
> > out at
> > about 91 mph, and since the top speed is really 88 mph in reality,
> > that's
> > close enough for gov't work.
> >
> > If anybody wants the final results, drop me a line and I can send it
> > along
> > to you.  Once I have something close to complete, I can upload the
> > graphs at
> > my Imagestation albums.
> >
> > To add more engines, all you would need is dyno data and gear
> > ratios.  Punch
> > it in on the spreadsheet, do a little Excel work, and bammo - a new
> > comparison is born.
> >
> > Chris
> >
>
> ________________________________________________________________
> GET INTERNET ACCESS FROM JUNO!
> Juno offers FREE or PREMIUM Internet access for less!
> Join Juno today!  For your FREE software, visit:
> http://dl.www.juno.com/get/web/.
>