rweatherford

I tried to measure everything out the other night on my Miata. I have been going pretty regularly this year trying to get used to the car before changing much.

Current parts list as purchased from previous owner.

15x7 wheels
Dunlop Direzza DZ101 205-50-15's (34-32 PSI)
Flying Miata front (hard) and rear (soft) sway bars (removed rear for one event)
Tokico HP Shocks and Springs
Front is 12" or a little lower
Rear is about 12.5"

Best I could measure with strings, levels and a dial caliper is as follows. Yes I adjusted for the 10mm difference in track and leveled the floor with shims under the tires.

Camber

LF = -1.71
RF = -1.91
LR = -1.95
RR = -1.87

Toe In

Front = 0.071" or 0.25 degrees
Rear = 0.126" or 0.45 degrees

My general feelings driving the car are it understeers turning right and oversteers very slightly (perhaps just under power) turning left. I did not like removing the rear bar as it made the car seem vauge in the rear and understeered on corner entry and I felt like I was loosing a lot of time waiting on the car to turn. However the car is a bit skitterish in the rear under power with the bar attached. It is currently back on the car. This car simply does NOT like bumps.

I have another event this weekend and wondered if I should go to the trouble of changing things or just keep driving.

Main problems are low total grip in turns and transitions that race tires would really help. Oh yea and the driver....

rweatherford

<crickets......>

Anyway upped the left front tire up to about -2.5 degrees and adjusted toe and it seems to be just very slightly in. I think the caster bolts are turned about the same on both sides in the front. The camber bolts are also similar, but the left is measuring more camber. Right side is showing about -2.0 according to my measurements.

I saw a page today that had clear tubing taped to the wheels with water in it to make the car level, seems that might be the best way. All the tubing was attached so the water could flow to each wheel.

A cheap angle meter might be the best item to buy from Harbor Freight. I'm not super concerned about thrust angle for now, but I might go to the trouble to measure it all out sometime.

Rear is set at about -2.1 left and -1.9 right with 150 lbs of marble floor tile in the drivers seat and footwell.

rweatherford

Car turned great today and the rear was a bit loose but controllable.

I think the next stop is NB top hats and different bump stops to allow more compression. I think this is killing the handling.