Re: AWD und FWD

["Al Powell" <apowell@agcom.tamu.edu>]

Our colleague Randall C. Markarian said:


> > Actually, I don't think you can reach a valid conclusion by
> > using any production vehicle as a basis for this discussion.
> 
> Excellent point, but not a race car either.  

Agreed.  ALL are designed around a specific purpose and specific 
drive type.

> Remember the original arguement is that AWD is just not significantly 
> (missing words here??) in  the dry on regular cars(<350-400hp).  
> Would you give up your car based
> on that? Neither would I.  Guess who said that?  

Don't care, honestly....  ;-)

> I said that AWD IS  superior all of the time.  

First, define "superior".  It adds weight and rolling resistance, 
thereby slightly increasing fuel consumption.  Not superior in terms 
of fuel economy.  However, it does add stability and traction in 
low-traction situations, and changes handling characteristics in a 
way which some drivers find highly desirable in high-performance 
driving situtations.  Therefore, superior for those applications.

As analogy, a superior screwdriver (well-made, good metal, accurate 
edge) is not a superior hammer.  But if made with a sufficiently 
strong and dense handle, and be made to serve as a hammer 
sometimes.  For applications truly requiring a hammer, a screwdriver 
will not serve as well, if at all.

> How do we prove it?  What is your null hypothesis? 

Hmmm...  good question.

I think you have offered the following null hypothesis:

"There is no significant difference between the serviceability 
(select your own verb, not sure this captures the meaning) of a 
vehicle which has been designed for FWD and its serviceability in an 
AWD configuration."  

Then if we find there IS a significant difference, we reject the null 
and conclude that there IS a significant difference in AWD 
configuration.  The discussion seems to be whether a valid test can 
be devised to test for significant difference.

So let's see, my null hypothesis might be (I'm in a hurry and don't 
really have time to think this through...):

"There is no valid way to test for serviceability of FWD and AWD in 
the same vehicle, given a conversion of drivetrains with no other 
changes."

If we found there was a valid means of testing, we would reject the 
null and conclude I was full of road apples (a possible conclusion 
already!!)

Sheesh.......


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