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Re: Corner Weight Checking Scales

Terry Lee says:
>I've been reading Fred Puhn's book "How to make your car handle",
>and it goes through a procedure to "balance" the weights in
>the corners as a starting point for further suspension tuning.

"How to Make Your Car Handle" by Fred Puhn really is a great book.
At first glance it seems kind of dated (1981), but it's well written 
and covers the basics clearly (available from Classic Motorbooks 
800.826-6600 for about $16.00). 

>It calls for the use of scales to measure the load at each
>tire...Outside of purchasing a set of four electronic race
>car setup scales at $1300-$2400, what options do I have..

Terry is talking about checking and adjusting the "corner weight"
at each wheel so the car is more balanced, not the total weight.
This is usually done by slightly raising (more weight) or 
lowering (less weight) the ride height at each corner.  Ride 
height changes affect weight across the diagonal of the car.  
For example, raising the left front, increases the weight on 
both the left front and right rear tires.  

The hard part is easily adjusting the ride height.  Unless you
have adjustable spring perches, it's pretty tough.  I've thought
about measuring my corner weights, but until I can do something
about it, I don't want to know.  Mentally, cars always handle 
much worse if you know something isn't perfect.

The cheapest way to measure corner weights is with a single 
"corner weight checker", a simple lever with attached pressure 
guage that lifts at the wheel rim.  Weights are checked one wheel
at a time.  I've read that they are not very accurate or 
convenient to use ($230).  

However, famous race car tuner and author, Carroll Smith 
recommends (can't remember which book) the "RuggleS'cales" 
as the best compromise between cost effectiveness and ease of 
use.  The system consists of four multiplier brackets with 
individual inexpensive scales.  The car is driven onto the 
brackets and all four corners are checked at once ($395).    
 
Both of these systems (and the more expensive electronic devices)
can be found on page 100 of the 1996-1997 Pegasus auto racing 
supplies catalog 800.688-6946.

  Regards,

  Pete Read
  '88 M5