Separate back up button?
 

Does anyone use a separate back up button to put their PG solenoid in to engage reverse without engaging the delay box/throttle stop or starting line control cylinder?
I'm thinking I could wire one in the circuit with a diode preventing feedback to the delay box but I don't have any knowledge concerning diode sizing or ratings etc.
Can one of you Guys help me out with this?

Re: Separate back up button?
 

You don't need a diode. The 12V when put to the transbrake is on the output terminal of the delay box and does not cause any issues in the delay box.
Dan

Re: Separate back up button?
 

The Don Davis race car wiring diagram is setup that way for wiring the Davis cars.
I wired my own and did not use the separate button/switch because I thought it might accidently get tripped while moving to the staging lanes in low gear causing a real issue.
The wiring diagram showed a simple on/off switch and I have looked at a few Davis cars which had the switch mounted on the dash panel.
I just chose not to use one.
Just My 2 Cents
Rick Cates
Canyon, TX

Re: Separate back up button?
 

I've used them in the past. I just used a toggle switch mounted on the dash, that way there wasn't a chance of accidentally hitting it while driving around, and I didn't have to hold the button down while turning the wheel.
Dan

Re: Separate back up button?
 

One side of button to +12 volts, the other side of the button to the Transbrake terminal of the delay box. That's it; no problems.

Re: Separate back up button?
 

Could you use a momentary switch. You would have to steer with 1 hand and hold switch to go in reverse. That way you will never forget to flip toggle switch.

Re: Separate back up button?
 

I use a toggle switch on the steering, just parallel the transbrake button. I use a red aircraft cover which protects the switch from being accidently hit.

Re: Separate back up button?
 

In my dragster, I use a small microswitch on the top framerail in the cockpit. I can only have one hand on the steering wheel, but turning the wheel doesn't affect my ability to hold onto the button.

Re: Separate back up button?
 

If you use a toggle switch, you won't forget that it's on. As soon as you put the trans in low gear, to move forward, the brake will be applied. Then you know you have to turn off the switch.
Dan

Re: Separate back up button?
 

My trans brake button I use to back-up is mounted on a bar overhead right next to my dome light.....It isn't hot all the time...I flip a switch to put power to it, back up and then turn the switch back off..