The cure for B14 Chronic Understeer (I think)

[mike kojima]

I have been building and racing B14's for quite a
while and have never quite been able to get all of the
understeer out of the chassis and to make the car
respond crisply to attempts to get it to rotate.  I
have gotten them to where they rotate slowly with
bending the beam and with ridiculous spring and rear
bar rates but they will still have terminal understeer
if driven in a ham fisted manor.

The B14 is also sort of squirmy under trail braking
and turn in and also has a vague feeling in the rear
while taking a set.

Well I was looking at the trailing arm bushings and
noted that they were made of really gushy rubber and
had large windows cut out in them for additional flex.
 I figured that these bushings were allowing the axle
to walk around giving the insecure feeling in the back
and also decoupling the antisway bar and the torsion
bar of the rear axle.I had Energy make me a set of
urethane solid bushings to replace the rubber.

The results are oh my god! The car is now so
responsive I spun it on the track on my first lap,
just warming up the tires.  The car was way too loose,
a first for a B14.  After some shock and tire pressure
adjustment, it was a lot better but still quite loose
and I managed to spin in the race when I had to take a
turn off line to avoid spinning cars.

I feel that this will make a big breakthrough in
B14-B15 handling, i just have to resort my car to take
advantage of the better response but reducing
oversteer a little.  I am going to soften the rear bar
and perhaps the rear springs.

These bushings are like going up 300 in/lbs in rear
spring rate!  They make a bigger difference in chassis
balance than anything I have done so far.  They also
eliminate the squirm and weird feeling out back.

Energy should have them for sale soon.  As a warning,
although they should be nice on a street car, if you
have an already on the edge tuned race car, its going
to knock you into wild oversteer.

Mike