It might we worth looking at this thread which has similar content.
http://www.mp3car.com/vbulletin/hard...ed-guages.html
It shows a couple of early screens for my race car taken last year.
Regards gauge update times - I found that for numeric values anything more than 0.5 seconds is pointless as you can't "decode" the information fast enough. If you need faster updates than use some sort of graphical display - even then I find that updates more often than 0.2s just become noisy. Also make sure all gauges support flexible damping / smoothing / filtering algorithms (I use all 3 for different gauges) again this helps reduce noisy fluctuations around a base point.
Take for example, my "curved" rpm gauge, each bar segment is 100 rpm and it updates 5 times a second, I also now show rpm rounded to the nearest 20 rpm (not shown).
For my actual race screens, I only show RPM, speed - more for the benefit of in-car camera than me to watch (I use shift light reflections on the windscreen to determine gear shift). The only race specific gauge shown is stopwatch (autostarts when the wheels start moving and stop when the course length is reached) and a BIG segment bar showing the amount of time I am up (green) or down (red) on my best course time. Anything else of importance is flashed up in an alarm window and logged for posterity.
The only other felixible and costly commerical systems I have seen are the ones from Cougar Data Recording
www.cougardatarecording.co.uk and X-Dash from
http://www.dtafast.co.uk/XDash.htm.