I'm cross posting this over here from the C7 Z06 section. It seems like most of the folks that track a C7 hang out over there but I know we see some C7 questions over in A&RR as well. For you seasoned racers I'm sure this will seem very elementary but I hope it helps the folks not familiar with how to use the Cosworth toolbox.

I'll be adding additional examples down the road in the original thread here:
https://www.corvetteforum.com/forums...-with-pdr.html


So you've gone to the track and you've recorded some sessions with the PDR. Now you're looking to get faster and wondering what to do with that data you've collected. I wanted to share with the forum a little bit about how I use data to improve my lap times.

I'm going to do this post using the PDR and Cosworth toolbox since most C7 track rats have that in their car. However, the Cosworth toolbox is pretty limiting as far as data analysis goes even though it collects a ton of great data. If you're serious about using data then I'd also recommend getting an Aim Solo DL and running that in parallel on track as it makes it much easier than the PDR. I keep hoping that GM or Cosworth will make some enhancements to the toolbox to make it a more full-featured data analysis product. I'd even be willing to pay for it.

So for starters, make sure you have the MP4 files you want to analyze downloaded to your computer from the SD card and also make sure you install the Cosworth toolbox available here:
http://www.cosworth.com/toolbox/

There's also a video posted by Cosworth here that goes over some of the more basic functions in case you need help:

Now my general approach to data analysis is pretty simple. I'm not perfectly consistent lap to lap and I suspect most of you aren't as well. Even when my lap times are very close I've noticed that I'll do some things better or worse on two laps with very close times. My goal is to find those areas and then learn from them to understand what makes my fastest ideal lap. I do this by comparing my fastest lap with my 2nd, 3rd, or 4th fastest laps to identify those differences. So let's start with a real example.

Open up the Cosworth toolbox and select your session with the fastest lap as the "Reference Recording" and the session with the lap you want to compare as "Recording". If you're just starting out it's best to choose laps from the same day so that you know that track conditions (grip, temp, humidity) and vehicle conditions (tires, brakes, suspension) are largely the same.




Now that you have the files open let's go to the view that I will primarily use in the toolbox. At the top select "Corners" and "Chart". Off to the right the Channels you should select "Driver Input". Make sure the laps you want compare are selected at the bottom and finally make sure you select "Distance" not "Time". That compares the two laps based on distance travelled rather than time elapsed so in theory you are always comparing the same two places on the track.




Now, most of my effort will be focused on the time delta graph and the "Corners" view is the only one that will show you that data. You might notice that the time delta suddenly jumps up at the start by ~.2 seconds and then back down again at the end of the lap. I have no idea why the tool is showing that but in the end the result is the same so it won't affect our analysis.

If you look at the time delta at ~1600 ft in to the lap it shows about a 0.2s delta and by ~2900 ft it's down to 0.03s so there is nearly two tenths I gained. By clicking in the chart in the middle of that area (~2200 ft mark) and hitting the 'Z' key you can zoom in on just that section. You can also use the +/- to zoom in on the map - in this case to where I started gaining ground.




I noticed a couple of things about this. First, my line here is closer to the apex curb for longer. That in turn lets me get back to full throttle sooner but I also have to breath off of it. In my reference lap I get to full throttle later but once I'm there I stay in it. In theory, the latter technique is correct but is it?

If I toggle the "Channels" tag over to "Forces" it allows me to see the speed graph. Now the speed graph itself is pretty worthless because it does not autoscale like the other graphs and is always 0-200 MPH. That's pretty worthless when you're trying to see a 2-3 MPH difference.
However, you can see the actual MPH off to the right and use the arrow keys to move along the graph and see how it changes. In this case, you can see that while my speeds at apex were the same that little shot of WOT allowed me to pick up ~ 3 MPH and I carried that speed delta all the way until I started to brake for T3. That's where the time gain came from but unfortunately I gave it all back by over slowing for T3 (min speed 5 MPH slower than my reference).




I think this is a good place to stop for now and I'll add another post later. However, I discovered one other interesting point while looking at this data. I am way overslowing for T1 and getting back to throttle too early. Look at this capture.




As you can see I am back on the throttle and accelerating before I'm even half way to the apex. I should be carrying speed through there and gradually slowing the car until the end of the inside curb, then getting back to the throttle. In this case I don't have a lap to compare to know how much it would gain me but it's something that I'm going to focus on next week when I'm back at VIR.

Finally, here are some Cosworth keyboard shortcuts I've found:
Chart
Z - zoom in
Backspace - zoom out
M - max speed jump to
N - min speed jump to
R - rate of change and can highlight section
T - tile

Map
+/- zoom in and out
Arrow keys move around the map