My boost controller will accept a 3.5v - 12v square wave RPM signal from an ECU or ignition coil.

I had originally planned to run a PWM output set as a Tacho, but when I connected everything, I don't get the rpm signal.

Does anyone know if that Tacho PWM output send the square wave signal? or should I just pull it from the trailing coils?

 

Are you running the stock FC coils?
It's easier just to tap off the female bullet connector off of either...


-Ted

 

Yes, stock FC coils. It's the yellow wired bullet connector on the trailing, correct?

Either coil will work fine, correct? Or is it better to pull from one over the other?

 

Yeah, either from the leadings or the trailings will work, but...
They fire differently.
The leadings fire like a 4-cylinder - 1 pulse per RPM.
The trailings fire like a V8 - 1 pulse per 2 RPM's.

Can you set your boost controller to accept either signal?


-Ted

 

Ok. Thanks.

Yes, boost controller can be switched for different cylinder applications.

 

Hooked into the yellow bullet connector wire off the trailing coil. The RPM reading is off if I select 8 cyl, but is spot on if I select 4 cyl.

Also, A few times, the RPM would read some CRAZY number like 9800, and up to 12000 at one point...I can verify this using the peak hold rpm call-back function.

Anyone have any ideas? Coils going bad?