Lotus Wheel Alignment (Flyin’ Miata)

So… with the ride height and corner weights set and a preliminary set of alignment values I set about switching out the wheels for the Flyin’ Miata hub stands. While the hub stands have some big advantages (as we’ll see in a moment) setting ride height and corner weights on the stands would require some sort of “conversion” to account for the height of the stands and “rolling radius” of the tires (it’s not 1/2 the diameter and depends on tire pressure). Fortunately the combination of a scissors lift and wheel stands makes switching over to the hub stands quick and easy. The image below shows the Toe Bars on the hub stands with Carl’s thrust angle string system installed.

The first order of business is re-calibrating all four Toe Bars from the wheel hubs…

Then setting up to measure toe using tape measures between the hub stands underneath the car, and thrust angle using the strings.

The first round of hub stand Toe and thrust angle measurements agreed reasonably well with the values recorded from the ART laser toe gauge. In fact the measurements from the rear were nearly exactly the same (Toe IN: .062”) while the front showed a larger Toe OUT condition (.25” vs .20”). While I can not explain exactly why this occurred at least it showed the the error in the same direction… just a little more of it.

The image below shows the Flyin’ Miata hub stand system in place on the front right corner of the Lotus Exige.

By moving around the car a few times taking Toe angle measurements from the hub stands… I made sure the measurements repeated nicely. I then decided to bust out a set of wrenches to adjust the front tie rod ends and bring the front wheels into alignment.

Having the thrust angle strings right there in front of you while making adjustments to the tie rods is very nice. The fact that you can reach down and check the tape measurements anytime as well makes this process fast, intuitive, and confidence inspiring. With the car at waist level and wheels of the way the task is almost too easy. A couple of trips from side to side and about 3/4 of a turn with the wrenches brought the front wheels into alignment.

With the rear wheels consistently measuring Toe IN: 1.5mm I decided to leave them alone and moved on to removing the hub stands and putting the wheels back on the car for one last measurement with the ART Laser Toe Angle Gauge.

The results…

• Front: Toe OUT: .5mm (2 minutes)
• Rear: Toe IN: 1.5mm (12 minutes)

Or…