Correct on the Digital Delay. With their Elite Board, No additional solenoid needed. I've used it that way on our last 6 cars.

^^^^^^ Here’s the wiring chart for the DD V10 Elite relay board. It’s listed as supporting up to a 60 amp shift solenoid.

I use this same V10 Elite board. Because my shift with air is directly wired to the electric over air solenoid with a diode for flyback voltage, I do Not use the Shift Output control on the board for this function. Instead, I use it to run the Line Lock in a unique wiring method. When activating the line lock with the button for burnout it does not activate the transbrake or 2-step. When the transbrake/ 2-step is activated, the Line Lock is also activated with it.

When +12v is applied to the Select terminal, the input switches from RPM to Time. When +12v is not applied to Select, the RPM terminal is active. vvvvvvvv

thanks for the input. thought i was good as we we are just providing low current to a high current relay.

When using an external relay, thoughts on switching the negative to the shift solenoid instead of the positive to reduce arcing in the contacts in the relay

All excellent ideas and input --- thank you.

In regards to using the negative side for switching to reduce arcing across the contacts, a DC circuit has the same current (amps) going through it on either the positive or negative side of the circuit IF it is a single, simple circuit. Meaning all you have is one device being turned on or off in the circuit.