Quote Originally Posted by 1project2many View Post
There was a TCM only controller used in the early '90s in trucks equipped with a 6.5.

The crank sensor signal used with 0411 is a 0-5V square wave signal. The HEI module provides intermittent ground to the tachometer to signal an ignition event so additional electronics would be required. The HEI REF signal is a 0-5V square wave signal that might work to trigger the 0411. Is the engine EFI or carb equipped?
The engines will be non-EFI with no reluctor ring or ability to sense crank speed. MSD does make a sensor that can be installed on the damper but unsure if it has been used. Would be real simple if we could use the distributor. I’m interested in finding fol;ks that have done this with some level of sucess.