I use Harry's Lap Timer and Race Render along with an external 'dual xgps160' 10 hz gps.

Harry's lap timer:
http://www.gps-laptimer.de/Home.html

Race Render AND Track Addict:
http://racerender.com/Products/index.html

Currently my 'best' video has gps and accelerometer data. Skip ahead to 2:40 - no data is on the screen prior to the first recorded lap starting. Not the greatest run.
http://youtu.be/xgDN7LoFVjs?list=UULmauI0f-d_etqBKwN98jrA

I have since purchased a bluetooth connector for my megasquirt and a nexus 7 tablet. That should log all engine data, which can be married up in racerender with Harry's data.