Packard Forum Index » Modification Discussion

Very different units mechanically and electrically. Easiest way to tell what's in the car without going under is look at the relay in engine compartment. It's about midway on drivers side of firewall and slightly above the starter motor level.

R9 has a roughly square black box slightly larger than the voltage regulator and having 6 terminals.
R11 has a smaller usually a natural metal color rectangular box and having 4 terminals with a fuse on the side.

Under the car, the R9 has the lockout lever and a 4 terminal solenoid on the passenger side. R11 has them on the drivers side and is a 2 terminal solenoid.