Has anyone ever hooked up a tachometer on a T. If so, any advice on how to do so would be very much appreciated.
I am going to send you a private message about your question.
I would really like to find a tach for my T that has a distributor. I would like it to have a 0-3000 RPM scale. Anyone know of such animal? A 3" analog dial would be desirable. 6 or 12 volt would work.
Hi Pat. Buzz Pound used to market one years ago and I wish they were still available as I sure want one. I don't know for sure but it was probably a frequency to voltage converter chip .... possibly a LM2907 but my memory on that isn't good. I have some of those chips around somewhere. I think he used a 270° sweep style voltmeter.
Anyone have a good working Buzz tach for sale?
I bought a modern Equus tach a few years back as it was entirely programable and I thought it might just work ... it didn't. Maybe it's like the signal lights problem - you need some good shielding and then keep the darn thing as far back from the dash as possible.
Others have had success with a small digital tach but I don't recall the name. I'm sure someone will post about theirs .... Tinytach - that's it.
Oddly enough, my GPS powered speedometer works perfectly in my racer. It was a fair amount of money to spend on a 'maybe' but it turned out well. Good luck.
The only 3000 rpm tachs I found have lousy reviews.
I can attest to the quality of the AutoMeter tachs as I own two of them.
4000 rpm tach: http://www.summitracing.com/parts/atm-2890/overview/
Perfect for a distributor system as one lead connects to the coil.
I've considered putting one of these on, but haven't gotten around to it yet. I know they are popular with homebuilt aircraft builders.
Eric, The only problem is that it only registers 19,999 RPM.
Gene, that's to help you keep your T under the speed limit on the Interstate.
Thanks for all the great responses! I asked the question for a friend and will pass all the responses along to him.
The Buzz tach used a 270 degree meter and a single IC, 7400 six element inverter. Three are wired as a shaper and the other three as a pulse generator. The output of the pulse generator, one pulse for each opening of the points ( or whatever) is averaged by the analog meter. Much more simple than I every thought. Of course Buzz was as smart as they come, he really was a retired neuclear scientist. He stopped making them when a cheap supply of the meter dried up. He was the brain behind discovering that the timing on a T using magneto is either 4BTDC or 11 ATDC irrespective of where you put the lever. He and Don decant wrote an article about this in the Vintage Ford some years ago. Both have now passed and I still miss them....
I wonder if you could use the tach out of a small airplane. The little flat fours typically redline at 2500-3000 RPM so the range is about right.
I do not understand the statement: "the timing on a T using magneto is either 4BTDC or 11 ATDC irrespective of where you put the lever."
I would think if you place the spark lever in the full retard position one would have a better chance of catching the 11 ATDC firing and if one put the lever in the full advance position one would have a better chance of catching the 4BTDC.
I do not understand why the spark lever position has no value.
"the timing on a T using magneto is either 4BTDC or 11 ATDC irrespective of where you put the lever"
That doesn't make sense as the timer position determines where it allows the coil to fire.
Read this and all will be revealed....
Well that article sure overrides what TB said: "irrespective of where you put the lever"