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tachometer for V8 conversion
- Thread starter philman
- Start date
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Hi Guy! I probably shouldn't be replying as I probably know or think I know just enough to contribute nothing of substance. Seems if you just hooked the 4 cyl tach up to the 8 cyl it would read double the RPM which might make it workable as the scale goes to roughly twice the 8's RPM capability.
Niether TRF or VB show the TR8 tach as being available, but Rimmer Bros. shows TKC2587R as being stocked as a recalibrated unit with a surcharge or core charge. There might be a way to recalibrate the 7's tach to read the right RPM by adding resistance to the internal circuitry. This is how the Dixco tachs were factory calibrated 30 odd years ago. They were first calibrated for 6 cylinders then another resister was added to calibrate for 8 cylinder operation. The second resister was then painted with red nail polish so that the same tach would work with 6 cylinders by removing the lower or "red" resistor. If the right place in the circuit of the 7's tach could be located a variable resistor could be added and the tach calibrated with it. The earlier Dixco tachs were calibrated this way until the large calibration desk was built with all the cubbie holes for the 2 dozen or so fixed resistors.
Now, this is probably all the useless info you can stomach so I'll cease my ramblings. Good Luck
Niether TRF or VB show the TR8 tach as being available, but Rimmer Bros. shows TKC2587R as being stocked as a recalibrated unit with a surcharge or core charge. There might be a way to recalibrate the 7's tach to read the right RPM by adding resistance to the internal circuitry. This is how the Dixco tachs were factory calibrated 30 odd years ago. They were first calibrated for 6 cylinders then another resister was added to calibrate for 8 cylinder operation. The second resister was then painted with red nail polish so that the same tach would work with 6 cylinders by removing the lower or "red" resistor. If the right place in the circuit of the 7's tach could be located a variable resistor could be added and the tach calibrated with it. The earlier Dixco tachs were calibrated this way until the large calibration desk was built with all the cubbie holes for the 2 dozen or so fixed resistors.
Now, this is probably all the useless info you can stomach so I'll cease my ramblings. Good Luck