I have been testing for the last few years with the Race Technology AP-22, which is a nice accelerometer based performance meter. Recently I have acquired a Race Logic PerformanceBox, which is a gps-based performance meter. The PerformanceBox is targeted as a consumer version of the Vbox unit that some car magazines use for acceleration testing.
The first tests I ran with the AP-22 back when I acquired it were to test it side by side with my previous test unit, a Tesla G/Tech Pro. The AP-22 has the advantage of providing more detail about the test run, in that it provides 0-10, 10-20, 20-30 mph acceleration etc up to the max velocity set for the test. The earlier G/tech Pro only gave 0-60mph or 60 ft, 330 ft as part of a quartermile run. Having the greater detail of the intermediate results makes it much easier to determine exactly how a modification to the Cadillac has effected performance.
So, my next test need to be side-by-side comparisons between the AP-22 and the new PerformanceBox. That will help me consider future runs with the Performancebox in context with the history I have from testing with the AP-22.
I would like to make the tests with Premium fuel and the current, unmodified suspension setup. So once I have run through a tank of premium I should be able to get the acceleration testing done. Then I can work on baseline lateral G-force test setup and execution with the base / stock suspension. Finally, we can re-run the lateral G-force tests with the CTS-V sway bars in place.
My intuition is that I will also need to decide how to handle the runs with regard to roll-out. Roll-out is the first 10-12 inches that on a traditional quartermile track, due to deep staging, a vehicle can move before it triggers the timing system. Rollout tends to make a 0-60mph measurement 0.4-0.5 sec faster than if it were an absolute measurement from 0 feet. Because magazine tests used 0-60 times from their best quartermile time measure, their 0-60mph times also used the same rollout assumptions. After some thought on the topic I suspect the best solution is to show the data both ways. The PerformanceBox datalogger makes it easy to determine the exact time that the car reached around 1 foot of travel, and this time can then be provided as an offset to the data. So the data can be shown with and without rollout.