direct fire FC3S tach resistor
 

Does anyone that is running direct fire on their FC with a select ecu know where I could purchase the proper "pull up resistor" to run the factory tachometer off the ecu? I haven't had much luck searching..thanks

Definitely interested in how people do this. I'm going to approach this simple interface problem on my 1st gen next year. :nod:

If I remember correctly, 550ohm 1/4w axial lead resistor is all you need.

I think i have spares

I have an FD, but this was the solution. From reading the manual and the supplied diagram/schematic it should be the same.
You Y together a 12V with resistor to the Aux Out of the ECU into the tach signal receiver.

I think the difference would be how it is interpreted at the tach, i.e. FC/FB.
I have seen 93 FD Tachs that do not read as precisely with a Microtech. i.e. being a few RPMs off (higher)

https://www.rx7club.com/adaptronic-e...iring-1079455/

Based on our recent conversations, this should not be an issue for you. Proper in-built circuity solves a lot of issues.

Yes, I'm excited to see what this VEC and new ECU can do for me once I realize the flexibility of setup. Integrating OEM gauge interfaces and controls with new hardware is really going to be nice.

Yes for the Select ECU's a 560 ohms resistor T into the tacho output wire that goes to the dash. One side of the resistor has 12v the other connects to the Tacho wire.

And in reference to to Mr. Ludwig's response the new Modular ECU's do not require the resistor.

Thanks,

Shawn Christenson