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QuantumMotorsports · 01-02-2001, 02:03 AM

I've converted a 4 cyl tach out of a TBird to work in my cougar, it's probably the same tach. You have to take it apart and switch out a capacitor and a resistor with different values. I'm still not sure if mine is quite accurate. It's close. If I were you, I'd recalibrate your 4 cyl (I'll tell you exactly how if you want, email me) and then I'd get an aftermarket tach as well so you know something's accurate. By the way, if you run with the 4 cyl tach on an 8 cyl car and you rev way up, you will eventually blow the tach. It's basically a frequency to voltage converter and then an analog volt meter. So the output voltage from the FV converter is way too high for the volt meter which burns up the coils in it. But you should be okay for a while. Tell me if you want more info on the recalibrating. I'd be happy to help.

------------------
Michael Black
Quantum Motorsports
Norman, Oklahoma

1988 Merc Cougar 5.0 HO, P&Ped heads, 2.25" custom mandrel bent dual pipes, T5 five speed tranny
15.43 @ 91.08mph (not shabby for a 3600 pound car)
60' 2.453 Street tires suck!!!

01-02-2001, 02:03 AM	#3
QuantumMotorsports Registered Member Join Date: Jul 2000 Location: Norman, Oklahoma, USA Posts: 597	I've converted a 4 cyl tach out of a TBird to work in my cougar, it's probably the same tach. You have to take it apart and switch out a capacitor and a resistor with different values. I'm still not sure if mine is quite accurate. It's close. If I were you, I'd recalibrate your 4 cyl (I'll tell you exactly how if you want, email me) and then I'd get an aftermarket tach as well so you know something's accurate. By the way, if you run with the 4 cyl tach on an 8 cyl car and you rev way up, you will eventually blow the tach. It's basically a frequency to voltage converter and then an analog volt meter. So the output voltage from the FV converter is way too high for the volt meter which burns up the coils in it. But you should be okay for a while. Tell me if you want more info on the recalibrating. I'd be happy to help. ------------------ Michael Black Quantum Motorsports Norman, Oklahoma 1988 Merc Cougar 5.0 HO, P&Ped heads, 2.25" custom mandrel bent dual pipes, T5 five speed tranny 15.43 @ 91.08mph (not shabby for a 3600 pound car) 60' 2.453 Street tires suck!!!