Inexpensive speedo options

[matt b]

I have been wanting to do some 0 - 100mph - 0 testing for awhile but, unfortunately, the little old Datsun speedo simply cannot keep up under hard acceleration. Are there any inexpensive options that are reasonably accurate up to 160km/h? I was thinking of a bike speedo type arrangement where you mount the sensor inside the wheel.
Thanks Matt b

[(pennywise)]

acewell speedo

as seen here
http://www.performanceforums.com/for...hlight=acewell

I use them on bikes, and work a treat