Tach reads 1/2 of what it should

[65blackfleetside]

Thanks for the Heads up guys. I will try flipping the dip switch on the tach from 4 cylinder to 8 and go back to the 1000 ohm resister.

Question about the factory ECM tach settings:
What does the factory setting on the Gen III ECM 4 cylinder or or 8 cylinder?

Why does every LS forum that I read including the Autometer website say to set the tach to 4 cylinder?