groundblock on firewall location

[prkaye]

I'll probably go with B&C's 24/48 groundblock. I figure it might be easier to mount this to the firewall before hanging the engine, but I'm uncertain where to put it. Does anybody have a photo showing where you mounted this, on a side-by-side A model?

[bullojm1]

Phil-

Here is where I put mine:



And a pic from the outside:



The only problem I have run into with this location is I cannot remove the battery without loosening the ground cable on the firewall attachment. I might make a longer cable so there isn't any interference.

Why not just go with the straight 48 terminal ground block? I can't think of any grounds you would need forward of the firewall. If you do end up needing one, feed it through the firewall passthrough and terminate it on the inside. It'll save you some money and weight.

[noelf]

I realize it is way early in the build process...from the photo above, do not forget about the LARGE ground wire (cable) that connects to the engine case and (ideally) the ground bolt that is shown on the firewall. The battery gnd cable and the engine gnd cable should share the same bolt connection.

The starter,when engaged, will consume a huge amount of power / current on the +12v cable to the starter. The current return path needs to handle the same amount.

[RV7Guy]

Hi Phil,

I put mine in a similar location to Mike. I would suggest moving it toward the center a couple of inches. The reason is you're going to be riveting another rib in there and you need access to buck the rivets without interference. Also need clear access to put the terminal on.

On that note, keep as much stuff away from top skin as possible. You'll be hating life when it comes time to rivet the top skin in place if you've blocked access.

[Mike S]

Originally Posted by RV7Guy

Hi Phil,

I put mine in a similar location to Mike. I would suggest moving it toward the center a couple of inches. The reason is you're going to be riveting another rib in there and you need access to buck the rivets without interference. Also need clear access to put the terminal on.

On that note, keep as much stuff away from top skin as possible. You'll be hating life when it comes time to rivet the top skin in place if you've blocked access.

Darwin has a very good point. Usually does in fact.

I might add, get as much of the stuff that goes behind the panel done before you rivet the top on. And, as he says, deep it low------not only for riveting later, but for access when you are laying on your back, attempting to work on something up under there.

[prkaye]

what about putting even lower, below that firewall stiffener piece of angle (mike has it sitting just above that firwall stiffener) ?

[Lycosaurus]

Originally Posted by prkaye

what about putting even lower, below that firewall stiffener piece of angle (mike has it sitting just above that firwall stiffener) ?

Will interfere with battery removal, unless you modify the battery case, as some people did (using a hinged door design to remove battery).

[RV7Guy]

Originally Posted by prkaye

what about putting even lower, below that firewall stiffener piece of angle (mike has it sitting just above that firwall stiffener) ?

It would probably work under, but close to the angle. Most of your wire runs will be attached to the angle as they get routed to the ground block, so it needs to be close. Also, there are brake lines and other stuff that will potential conflict.

Your engine block ground can hook to the other bolt.

[N941WR]

Take a look at this picture:

Notice how the oil pressure line runs above the battery.

To get the battery out, it has to be lifted up, moved towards the center, then up and out of the plane.

Not a big deal, just make sure you leave yourself some way to remove the thing w/o having to remove a bunch of wires.

Also note how the engine side ground block only needed two connectors. The inside block has over twice as many tabs and is full.