JBrown

Does anyone know of a piece that will convert a 12v tach signal to a 5v signal. My electromotive XDI system gives out a 12v signal. the MSD box I am using for my soliniod works off a 5v signal. I need something that will read a 12v signal and convert it to a 5v signal so my MSD box works right. Right now it activates the solinoid to close at low rpms but will not open it up at the desired rpm that I set it for. Know matter what chip I put in, it opens at 3900rpms. I am running into the 10s on my A/F meter. I would like it to say closed longer so I am not so rich at 4000-4500.

Thanks John