i got an MSD coil and installed it. i took the car out for a test drive. everything seemed to work fine. when i brought the rpm's up i noticed that the tach will not go up to 3500 rpm, then it will just shake. the motor will keep going, but that tach won't. i installed and then re-installed it just to make sure i did it right and i did. anyone ever have this problem. i also hooked all the wires up right to.

 

no problems when i installed mine, its pretty straight foward, dont know how someone could mess it up, it has to be something else besides the coil

 

i think it is pretty straight forward to. i don't know what the hell happened.

 

Follow that wire for the tach back. Sometimes if you bend the end wire at the terminal you will get intermittent readings. I mean as long as the car is running properly over that RPM I dont see how it could be the coil.