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I need observations from the people who have the better aftermarket Tach's in thier cars. Heres what is happening: I took the tach out of the Notch to calibrate it as I thought it was off... it was, over the whole scale so the center point had shifted... easy to touch up. But what came to be apparent was that when I put the tach in the oven and heated it to 50C (like under a dash on a hot day) the calibration shifted CONSIDERABLY... it red low when it was hot... about 300 RPM low at 50C! So then I started cooling each of the components... and none made any difference till I got to the COIL on the armiture... it made a HUGE difference... read low when it was hot and high when it was cold... by several hundred RPM! SO.... these low to medium quality tach's are all the same inside and VERY temperature dependant on calibration. My question is: do the better, more expensive (ie. VDO) tach's have a different way of doing it?? or a better coil that isnt so temperature dependant?? take and calibrate your tach to X RPM at Y Speed while driving your car in gear Z... at room temp and then let me know what you may observe when it gets really cold out.. or after you park the car in the sun on a hot day. I trust that the speedos dont change that much over the temp range so this would tell me if the Tach is. I would really like to build my next repro with better guts but hate to spend $150 on a tach that has the same issues with the coil. Hopefully... this will lead to a better evaluation of the "Freeway flyer" transmission!! Keith Keith Park Top Notch Restorations topnotch@nycap.rr.com 71 Squareback 65 Notchback 65 Squareback 75 Opel 87 Golf 88 Rx7 10th Anniversary ------------------------------------------------ To unsubscribe, E-mail to: <type3-off@vwtype3.org> For more help, see http://vwtype3.org/list/