Subaru 6 speed electric solenoid reverse lockout

[Dave 53]

Has anyone tried with success or failure to use an electric solenoid to activate the reverse lockout lever on a Subaru 6 speed?

[Rob T]

I did mine with a cable that had a twist-locking handle, with the handle located on the left side of the cockpit. R duty only. I wanted to make sure it didn't move after I set it. Also, there are positive mechanical stops for both positions at the transmission end. A solenoid is an interesting idea, but not something I would have tried.

[RPGs818SNA]

I think it can be done, and would be pretty cool. However, it will take some engineering to replicate all the safety features of the twist lock cable approach. The cable provides tactile feedback that it is working, visual feedback that it is actuated, and a locking mechanism to keep it from releasing inadvertently.

Mechanical push or pull type solenoids have short throws, like 10mm, low force, like 5 pounds, and can’t remain powered for more than 30 seconds or so. I can envision a solution that while unpowered, reverse is locked out. To be reasonably convenient while street driving, attempting to engage reverse should activate the solenoid, but a racing switch would prevent power from reaching the solenoid.

It might be easier to use a door lock actuator which is a motor that drives a rack one way or the other by reversing the leads. It doesn’t need (or tolerate) continuous power to remain in the locked or unlocked position, but would use a momentary DPDT switch to change position. To get a visual indication of lock, a push button switch located at the locking mechanism could activate a Locked light on the dash. To prevent inadvertent unlocking, a second non-collocated switch could deactivate the rocker switch.

Here’s an example of a door lock actuator controlling a coolant valve in an H configuration for my heater.
door lock actuator for heater.jpg

The final challenge may be to convince a race track inspector that it meets their requirements. Maybe a cable would be easier, although less elegant.

RPG

[Dave 53]

I took out my heated touring seat for the racetrack seat and the no longer used seat heater switch location would be perfect for a lockout switch. I think I'll try putting a cable pull knob in the same location.