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Weight distro considerations, Audi or not.



Having inadvertantly started the weight distribution thread through
considerations around a Rotary swap, I'd like to clarify the picture that was in
my head.  I wasn't thinking so much about weight distro as I was about restoring
the original ride height... or at least equalizing the ride height.  The
springs, OEM or upgraded, are designed to deal with a given proportion of masses
front to rear and anything else becomes a problem.  
As long as the car is static, or has no suspension inputs the problem is trivia.
 But how does one deal with the height equalization and keep the intended
suspension response. Cut a coil?  Well, that gets the front and back at the same
level but now you have changed the front spring rate.  (A coil spring is a
torsion bar curled into a more convienent shape.  The shorter the bar the
stiffer the spring.)  The rear spring is unchanged but now you have a somewhat
stiffer front spring supporting a somewhat lighter front end and the suspension
dynamics will require anti-nausia medication for the occupants.  One could
always move the suspension mounting points up or down on the vehicle.  Very good
idea.  When you've finished just let me know how easy it was.

Sure 50-50 may be an ideal distro but to get there perhaps it would be easier
starting with a clean sheet of paper vice an already sorted out automobile. 
Yes, one reads of instances where, "...and I took out the air conditioning
system and now the turn-in is... like... unreal!" An AC system may weigh 75lbs. 
On a 4000lb car with 60/40 weight distro, 75lb is only 3% of the mass at the
front end.  (Actually that calculation assumes all the mass is at an extreme
forward point instead of actually being distributed along the longitudinal
axis.)  Guess I'd be surprised if a seat-of-the-pants appraisal would be
entirely objective.  

But what if we removed 200lb from the engine compartment through an engine swap?
 Yes, the entire package would be lighter and the F/R distro would be 'better'. 
But I'm afraid one would awaken a number of suspension tuning dragons that would
require Xenia, warrior Princess, with an engineering degree and a large treasure
chest, to slay.

Regards,  Gross Scruggs