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Ford RPM 2 Datsun Tachometer


Guest firebern

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Guest firebern

Hey,

 

From what I have read there is a tranny speed sensor on the T5 tranny and the datsun normally gets the signal from the distributor. It reads of a resistor of 12kOhms and 1/2 watt, this is used to lower voltage

and current but just how much those the datsun tach need.

 

The T5 tranny has 1 wire for low VREF

so this would probably need to be set to the voltage and current the datsun tach needs and the other wire should wire up to the sensor wire of the datsun.

 

Does anybody read sometihing wrong here and those anybody have ideas?

 

Thanks,

Fire.

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The speed sensor on the T-5 is used for two things. First, the computer uses it to determine whether you are idling at a light or coasting. The computer has different fuel, spark, and EGR modes for idling at rest or coasting. The other use is for cruise control. The tachometer should be triggered SPOUT connection coming from the distributor (the SPOUT connector is electically equivalent to the negative side of the coil). You can pick up the connection at the driver's side firewall connector.

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Guest firebern

Holy smokes!

 

I sure got this one wrong. Ok so for the speedometer I got to grab the DG/Y wire of the eigth pin connector and plug it to the datsun Tach.

 

As for the tranny speed sensor, you are probably rigth. I just looked up the wires on the wiring diagram and it figures, they are dashed lines meaning they only came on California emmissioned models, I will have to look at this tonigth. I don't have the mass air flow sensor but maybe I have this speed sensor feature.

 

Thanks,

Fire.

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Guest firebern

I don`t quite get 'the driver's side connector'. Do you mean for the Datsun wire or the stang wire. I just tried to and there'S a major spark that comes out of that wire. Do I still need the datsun transistor?

 

Looking at the Datsun wiring diagram the wire is blue and shouldn't need the resistor.

 

So if i recapitulate I should wire the DG/y number 11 wire of the Stang to the blue wire that connected to the negative terminal of the resistor that is short circuited directly to the ignition neg coil. So, I shouldn't need a resistor then.

 

Can you confirm?

 

Cheers,

Fire.

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Guest firebern

All rigth,

 

I do get a signal, but it is very weak,

I need to weld those wires.

 

If you get a spark at every cylinder

then the Datsun tach will be counting

1 rpm for every six spark but the stang is every 8.So your actual RPM will be 3/4 of the tach's reading. Unless there is a fix I don't know about.

 

Later,

Fire.

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i think your correct there.. you will get it to work but it will be off..

i believe there is a resistor you can put inline to "adjust" it somewhat but it wont be real accurate.. but then the stock tack isnt that accurate anyway..

 

i'll be putting a 5" monster autometer and speedo in the dash .. easier.

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Guest firebern

Ya,

 

you are rigth on this one, it was probably easier. Can you replace the tach and speedo without taking the whole dash out?

 

I'll have to do it later, my speedo works.

Supposedly ford and datsun is a 1024/1000

ratio which is to close to really care.

 

Later,

Fire.

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