Grounding an orange box

[Barfyspitz]

 I'm getting ready to install a new orange box and ballast resistor.  what is the best way to ground the orange box?

[ODZKing]

The mounting of the case to metal/firewall or fender should be enough.

[Pete in NH]

I think there are a lot of cases where bad grounding causes the Orange Box to fail and the boxes are being blamed for poor quality.

If you look carefully at all the wiring diagrams you will see the return side of the 20 to 30,000 volt spark side of the coil actually gets back to ground through the Orange Box transistor. A bad ground on the box can put all that high voltage across the transistor and no transistor is going to survive that.

My Orange Box is mounted solidly to a fender well with 1/4 -20 stainless  bolts, nuts and lock washers. I removed some of the orange paint around one of the mounting holes and using a external tooth lock washer have a 1/4" ring lug with a wire on it that runs to one of the coil mounting bolts on the engine block. The lock washer bites into the box surface and ring terminal and ensures a good connection. That separate bonding wire ensures a good ground. Five years and counting so far and no issues with the Orange Box.

[Barfyspitz]

Thank you. Would running a wire from the mounting screws down to a solid frame work or does it have to be to the coil?  It's interesting I'm pretty sure the screws that mount the orange box Arsteel but when I went to put them in the magnetic tray they rolled right out! I wonder if this could cause a bad ground?  what would cause them to demagnetize?

[crj1968]

Probably not really necessary, but I used to always run a wire to the back of the box at one of the posts...you dont need to run it to a coil bolt, just any bolt on the motor, or all the way back to the battery ground. There are probably grounds on your firewall that are close by

[tan top]

what the other guys said /say  

also , as well as making  sure there is clean shiny metal at all contact  points , both sides of the orange box where the attaching bolt goes through & the sheet metal ! that it is attaching to ,  ( make sure you seal with wax / grease stop it going rusty/ flash rusting ) , I ran a dedicated thick gauge ground wire from the one of the orange box attaching bolts , back to the battery !  just to be sure if there was any trouble with  my orange box / ignition ! in the future ,  bad grounding would not be one of them .
   done the same to the voltage regulator also , but  just went to the rear ground cable bolt on the back of the head  ( i'm nuts  like that )