Miata Mailing List: June 1993, Message #8
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   From: (none)
Subject: Further Adventues of the Porsche-Eating Miata
   Date: (none)

Fellow Miata Dependents,
I thought I'd summarize the results of my recent alignment change to the group.
  Thanks to all who provide input to my initial request.  I finally settled on 
absolute zero toe front & rear, max front caster (3.7 and 4.1, L & R) , -.9 
deg front camber, -1.1 degree rear camber.

First let me say that I've been on this particular track (Summit Point) in
 this car many times in all kinds of weather.

The results were fairly impressive.  In general, the car was much more 
neutral (it had tended to switch between understeer and power on 
oversteer more quickly) and predictable.  Much more grip, control, and 
stability through corners.  An unexpected benefit was that the car did not 
get upset in the transition from acceleration to hard braking.  As a result,
 I was able to carry much more speed into turns off long straights, use 
the brakes later and more efficiently, and the extra cornering force 
allowed me to apply power sooner coming out.  I found myself going an 
extra few feet deeper each lap as I explored the new capabilities.  I was 
also getting better braking force.  Maybe the wheels were in a better 
position relative to the track surface to deal with loads created during 
braking.  In fact, I ended up braking so much harder and so late that I 
completely fried an almost new set of pads in four half-hour run sessions.
  I had to use the handbrake to get home, the front pads were literally 
down to the metal at the end of the day.  Had to resurface the rotors on 
Saturday.  I guess it's time to buy Ferodo's or Carbon or something.

Now for a more specific example.  For those of you not familiar with 
Summit Point, Turn 4 is a pretty scary downhill, off-camber turn at the 
end of a short, downhill straight.   I used to take it (gingerly) at about 1/2

 to 3/4 throttle in fourth gear, no brakes (maybe 80-90 mph).  The car 
would get pretty light as it ran over bumps and pavement changes in the 
track.  It was basically a hold-your-breath move.  Turn 4 exit dumps into 
an extremely short, steep downhill straight requiring major-league 
threshold braking,  and then into a tight left hand throw-away (Turn 5) 
which then leads into a series of S's.  Andy Poling had offered Turn 4 as a
 good reason not to get a "twitchy" autocross alignement, and I agree.  
Well, the new set up allowed me to take it flat out (foot to the floor), 
requiring even heavier braking coming into 5.

In general, I found I could brake later and carry anywhere from an extra 
200-500 revs out of every corner on the track.

Not a bad performance improvement for 70 bucks.

-Al