Thread: MSD tach adapter questions

Anyone have a tach adapter they use on their car with an aftermarket ignition setup?

I am about to buy one, but i have a hard time wanting to buy one because it looks like a transformer... something I can get at radio shack for $10.

So, is there anything special to these things? Anyone have one they can ohm out and tell me the resistance? Or perhaps someone has a better understanding of how they work.

Looks to me like a coil that creates a voltage spike in the power transistor to prevent a CEL from illuminating. Doesn't look that complicated at all... if that's the case.

So why is this thing $50?

I used the msd tach adapter never worked for me, maybe got a defective one I dont know but I still get the primary ignition circuit fault code. I would like to see where this goes also.

'fraid i cant help u on the msd but i have a similar quandary with the the s chassis peeps. there are all kinds of discussions about what dash to use or adapter etc when swapping in sr's. sr (s13 det at least) ecu outputs 0-5v on tach out. if your dash wants 0-12 then put a little pullup resistor on it. not really a particularly big deal, right?