I use a Gear Vendors overdrive with a 4 speed and there's a small delay between hitting the switch and the overdrive engaging. Has anyone done away with the controller and operated the overdrive solenoid directly? Does it speed up the change into overdrive? The only reason I can see for the controller with a 4 speed is to switch out the overdrive when I come to a stop. It's a nice feature but I would do without it if I could speed up the shift.

Should be a selection between "automode" on or off, on the controller so that you can engage/disengage the OD when desired,.......unless your controller has no "mode" control?

There's an autodrive position that's used with automatics but it's of no use with a 4 speed. I just switch the overdrive in and out when I want to. The controller switches the overdrive out when the car slows below about 15mph. It's just that there is a slight delay between operating the switch and the overdrive engaging and I was wondering if the controller was the cause. I was hoping someone had tried bypassing the controller to see if it got rid of the delay.

Mine also has what feels like a couple hundredths of a second delay when manually engaging the overdrive. I don’t know if the controller is causing the lag or if it is the solenoid. One sure way to find out is by pass the controller. It the lag is in the solenoid or the clutches I don’t think there is anything you can do to eliminate it. Years ago I had a Triumph Spitfire with overdrive. Basically the same set up as the GV. The Spitfire had a lag when selecting overdrive and it did not have a controller, so I’m inclined to believe it is not the controller causing lag. One more thought, I haven’t noticed any lag when manually disengaging the GV.

I know there is a small delay after the solenoid is operated while the oil pressure builds enough to engage the clutch but I thought there may be an additional delay from the controller. I find the overdrive disengages much faster than it engages too. It's not really a problem on the street, but on the drag strip it's difficult to time it so the overdrive engages at the correct rpm especially in the lower gears.

I don't know that it will speed the shift up any, but the OD unit will work just fine bypassed. My control box died when I had my GV in my old truck, so I just ran a wire to the foot switch and used it manually. All it need is 12 volts to the unit to shift in or out. It's smart enough to figure out which way you want it to go without the box Good luck.