Originally Posted by smitty477
"Actually I have a photo tach and found there are times I cannot get a reflective tape where I need it"
FWIW - I have had good results adding readable 'marks' to crank balancers, pulleys and even on the back of the engine on the flex plate 'teeth' with a small paint brush.
Taking a small can of chrome spray paint and spraying in into the can cap I dip the paint brush in and swipe a line in the desired spot - at times I have duck taped the small paint brush on a yard stick to reach in further. After that reading at a distance with the strobe without having to make contact was fairly easy. When used on slave pulleys you just need to know the ratio to do the math.
Good luck with whatever method you use
I got to do a little playing with my photo tac today. I used a silver sharpie and made a 1/4" x 1/2" square. It did pick it up but you had to be closer than with the normal tape. Also the rpm was showing 5 rpm higher than with the same size piece of reflective tape. 1871 vs 1876
I was impressed it worked at all.