I need to do some performance testing on a couple of cars. One is my TVR, and the other is a friend's TVR. Mine has VEMS already and his doesn't yet. We planned to fit a trigger wheel to his car so my spare VEMS could do data logging, but his wife is beginning to add up the cost of TVR ownership...
Is there a nice and cheap way to get a trigger input to VEMS using something like an inductive sensor on an HT lead?
All I need to do is monitor RPM with a reasonable degree of accuracy. The rest is maths.