[mrtonegto]

Bought some heavy braided straps off ebay and will be attaching them off the back of each head to the firewall.
The holes in the strap ends seem quite large, what's the best way to attach them to the
firewall?

[mtnbktrek]

....Bubble gum


j/k! Why not run them to the frame?

[mrtonegto]

That's a lot of chewing man!

Long way to the frame - they're only 10" long. Will be running another cable from the engine to the frame though.

[dmac]

Bubble gum will hold better if you duct tape over it.

But one strap to firewall should be enough, and one from firewall to frame. Shortest sheet metal screw you can get in the right diameter with a star washer. Clean and remove paint around hole, then paint after attaching strap.

[mrtonegto]

Bubble gum and now duct tape...............this is getting expensive.

I just read on another site that running a threaded copper rod through the firewall allows you to also ground the dashboard and all the internal gauges, etc. Sounds right.

[Old Goat 67]

Originally Posted by mrtonegto

I just read on another site that running a threaded copper rod through the firewall allows you to also ground the dashboard and all the internal gauges, etc. Sounds right.

This is just a wee bit overkill and painful.

[pfilean]

Proper ground straps for that use usually have different size holes in the terminals on each end. Usually about a 3/8 hole to attach to the head and about 1/4 to the firewall. The head end gets a threaded bolt into one of the accessory mounting holes not used on the firewall end. It needs a star washer between the terminal and the head to get good contact through the paint. Bolt will probably be one of those with a built in washer. Firewall end will use a sheet metal bolt and again a star washer to get contact through the paint. Pontiac did often put one on each head and some additional ones from the inner fender to the frame. The battery ground cable will of course go to the head. And I don't think I have ever seen a Pontiac that had a strap from the firewall to the frame. But I have not seen them all.

[mrtonegto]

Here ya go OG67:

http://www.painlessperformance.com/w...Fezm7Aod8woAZQ

For your pain....................

[GTOGreg]

Originally Posted by pfilean

Proper ground straps for that use usually have different size holes in the terminals on each end. Usually about a 3/8 hole to attach to the head and about 1/4 to the firewall. The head end gets a threaded bolt into one of the accessory mounting holes not used on the firewall end. It needs a star washer between the terminal and the head to get good contact through the paint. Bolt will probably be one of those with a built in washer. Firewall end will use a sheet metal bolt and again a star washer to get contact through the paint. Pontiac did often put one on each head and some additional ones from the inner fender to the frame. The battery ground cable will of course go to the head. And I don't think I have ever seen a Pontiac that had a strap from the firewall to the frame. But I have not seen them all.

This is the way it is on my 67. Different sized ends; small goes to firewall and is secured with sheetmetal screw, big goes to block and is secured with bolt to head.

Also, I have three ground straps on mine: a.) at the LH side from head to firewall, b.) from coil bracket to firewall, and c.) from frame to inner fender well near front of engine on RH side.

[Tim Corcoran]

Adequate grounding is frequently overlooked and can causes a multitude of problems if not done correctly. When it comes to grounding I would not worry about over kill.

[HWYSTR455]

The body box where the body mounts to the frame at the bushing is probably the closest point the frame meets the body.

Some of the ones that are on fenders and core supports are most likely due to the proximity of the horns and front lights.

Most are going to be relevant to the accessories near by that need grounding.

If the engine has good grounding to the frame, and the battery has good grounding to the frame, or both, and the body is grounded to the frame, there's not much more that needs to be done. You can ground the body to the frame in a bunch of areas, but it's not going to make a difference. Grounding the engine to the body at the firewall MIGHT improve electric gauge accuracy, but it's questionable how much.

If you're questioning the body grounds, look at how far away and the area the fuel gauge ground is. And it works.

.