Data acquisition

[steverife]

Who here uses it and what do you use?

And how does it benefit you?

I've used SoloStorm driving with Aaron and Kristo. It seems simple enough, but I don't really think it helped me figure anything out.

Also, is there any of the choices out there that can give me throttle percentage on a pre-OBD car?

[dewittpayne]

Harald Schlangmann of Harry's Laptimer has announced that there is work being done on a device to collect data like throttle opening from pre-OBD cars and transmit it in OBDII format for compatibility. See here: http://www.gps-laptimer-forum.de/viewto ... =11&t=1714

I use Harry's Laptimer with a BT1 OBDII dongle and a Dual XGPS160 10Hz Bluetooth GPS. I think a good way to look for places to go faster is the plot of total acceleration. Dips in the plot are where you might go faster, things like braking too soon and coasting before getting on the gas again.

Of course if you have a co-driver, it's better, as you can tell who's going faster where and probably why.

I think it's helped me, and even if it hasn't it's been fun to play with.

[steverife]

I might have to search your old posts, Dewitt. I remember you posting some things that were pretty interesting, but I was sort of anti-data acq at that point.

[rocracing2004]

I have used Race Keepers and its great. It gives me a lot more information than I really need though. The video inputs are great and with having four of them how many more angles do you really need?

RC

[dewittpayne]

One good thing is that unless you delete it, the data are always there. For example, here's the GPS plot from runs at Event #4 and #12 showing that the courses were indeed nearly identical. The main difference being the location of the starting line.

[John Brown]

And every corner in blue is much more pinched off... the start is the least important part of that course.. unless you have no power ..

[rocket71]

Isn't the left side there ran in different direction?

[John Brown]

no,its just where it overlaps.

[steverife]

Same shape of the course, but moving a few cones a few inches often totally changes how the course drives. This course totally drove different.

[John Brown]

Same shape of the course, but moving a few cones a few inches often totally changes how the course drives. This course totally drove different.

no data acquisition needed......... it went from a momentum course to a power course with just those small changes.. if the power cars had not fouled out.. the sissy cars would not have stood a chance in Pro Class.

and mainly why course design is so touchy.. a few inches here and there, change the whole picture.. Also, why I have never used much serious data in autocrossing.. Its too hard to duplicate a run. (or..I cant) Road racing its much easier.. plus , you get several attempts to "get it right"

[dewittpayne]

Even though it felt different to drive, the times were similar. FTD for #4 was Robert Carpenter @ 61.353 and for #12 it was David Disney at 63.561

Dennis Grant though data logging was useful. Of course his system was much more comprehensive including suspension travel at each corner.

[thrdeye]

dewitt, no disrespect, but 2.2 seconds on an autocross course is not even in the same ballpark.

[Wheelman_13]

From a driver development perspective, I think Data would be useful for autocross if you could have throttle/brake traces synched to video (so you could see steering/gear inputs). That would let you really take a hard look at your habits, and if you were someone with less experience letting a hot-shoe drive your car, you would be able to see what they were doing (and when) that made them faster than you rather than just confirming that they are faster than you.

IMO without the throttle/brake information in conjunction with a speed/time function, it's somewhat pointless for autocross.

On a road course, I've actually learned a thing or two just by looking at a speed/time graph because I can look at video and split intervals to see where I might have lost or gained time on myself.

All of the suspension travel/lateral G/etc. measurements might help with car tuning for that last 1-2% of performance.....but first you'd have to be good enough, consistently enough to actually be able to take advantage of a 1-2% better car. (I know I'm not)

[dewittpayne]

dewitt, no disrespect, but 2.2 seconds on an autocross course is not even in the same ballpark.

That was something of an apples and oranges comparison. Looking at the same car and same driver, we have Jim Simmons with a 65.908 in #4 and a 67.232 in #12; John Brown with a 66.328 in #4 and 65.066 in #12 and Paul Heathman 67.841 and 67.042. That's +1.3, -1.3, -0.8.

[dewittpayne]

Wheelman_13,

I get throttle from the OBDII port on the car via Bluetooth. Brake would be nice, but that would require a professional data logging system at a much higher price point. I'm looking for seconds, not tenths or hundredths. At #12, I estimate I was about 4 seconds slower than the car capability.