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I am trying to figure out the layout for the firewall. I am going with the Aerovee/Aerocarb, MGL RDAC, Aeroconversions oil separator, 48 place ground block, ST throttle (center), mixture per plans (also in the center). I am looking for photos and layout ideas where and how to get the throttle, mixture, electrical cables through the firewall. I have not ordered the engine yet but I want to get some stuff started. Also thinking of going turbo some time later. So I want to keep things clear if I do get the turbo. Any ideas and help is very much appreciated.

Gripdana wrote:I am trying to figure out the layout for the firewall. I am going with the Aerovee/Aerocarb, MGL RDAC, Aeroconversions oil separator, 48 place ground block, ST throttle (center), mixture per plans (also in the center). I am looking for photos and layout ideas where and how to get the throttle, mixture, electrical cables through the firewall. I have not ordered the engine yet but I want to get some stuff started. Also thinking of going turbo some time later. So I want to keep things clear if I do get the turbo. Any ideas and help is very much appreciated.

I have the left-mounted throttle, but other than that there are a lot of similarities. Here are some of my Kitlog posts. Click around and you'll find lots more.

http://www.mykitlog.com/users/display_l ... 54&row=110
http://www.mykitlog.com/users/display_l ... 01&row=105
http://www.mykitlog.com/users/display_l ... 725&row=95
http://www.mykitlog.com/users/display_l ... 320&row=84
http://www.mykitlog.com/users/display_l ... 290&row=39
http://www.mykitlog.com/users/display_l ... 3251&row=4

When laying out my firewall I forgot about the depth of the starter assembly. The smoke oil tank barely fit behind the starter. So make sure you take that starter into account when laying out the firewall. And make sure you have the engine mount on hand when you do the layout. You'll never get it right without having the mount to see where you need to work around.

If you think you may ever get the AeroVee turbo leave room for that, too.

Mike Smith
Sonex #439
17.5 hours after today :-)

Thanks Mike that helps a lot.

I don't think my firewall layout is a good candidate to mimic. However, I have one piece of advice to offer everyone about hanging stuff on the firewall.

Use nut plates to attach everything that bolts to the firewall.

It adds very little time or money to the build but it will save you hours in the future. Replacing things like ignition coils is almost inevitable and are tricky to do once the airplane is completely assembled without nut plates. With nut plates it is a trivial task.

Once I had everything in place on the firewall I detached everything, added the nut plates and reattached it all. The entire process took less than a morning and I have replaced several items over the years without any contortions or help. This is particularly true for items that sit up high on the firewall with access to the rear blocked by the fuel tank.

Good advice Bob, that's the way I'm building my ONEX. Either nut plates or stand offs that are riveted to the firewall for my terminal blocks.

David

I agree that using nut plates is a good idea. I wish I had done that on my XENOS. I needed to remove the coils once and it is difficult to get to the nuts on the inside because they are partially blocked by the fuel tank. So it's nut plates on my new ONEX.

-- Michael
XENOS N42EX (flying for 3 years)
ONEX (goal is spring 2015)

I plan to keep the right side open on my firewall, and use nutplates. Is there any reason not to use the very upper portion of the firewall? It seems as a minimum my regulator, ground block, and master solenoid could go there.

Here is my layout. I found several benefits from it.
1) the 6ga wire from starter, regulator, to batt is very short and easily run
2) the wires flow very nice across all the components
3) the RDAC is on a stand-off with nut plates to easily remove
4) the relay is on its own bracket on the top of the battery box which makes wiring runs minimal
5) the batt box is on its side so the batt can easily be removed

Thanks Josh! Good to have more pictures to study. Questions: where did you get your battery box? Should I wait and buy the battery closer to first start? What master relay did you use?

Bryan,
I purchased my battery box direct from EarthX. It is incredibly light (only 140grams) and ready for install. I knew it would save a lot of weight and time over fabricating my own. I created the bracket to hold relay out of 6061. If you are going with an EarthX, my opinion would be to pick up the box now so you can put it into position. The battery is good just sitting on the shelf, so I would buy the two together. They often give discounts if you mention Oshkosh. I think I got 10% my total order.

Also, you can find really nice lithium chargers for cheap which has the kicker function built in if you run the battery dead. Mine is a Schumacher Automatic. With EarthX, you just need to kick it to get it back, which has saved me about 8 times already. I really like the safety feature EarthX has built in.

Also, I would recommend you mark out your throttle cable, mixture cable and wiring pass-thru with minimal bends. Be sure to account for the fuel tank inside the firewall.

I picked up my relay from a Google online search as it's much cheaper than an aircraft store.
The model I am using is a White-Rodgers 70-111224.

Zoro is local and has it $28 shipped. If you search, you can find it for as little as $18 on eBay.

https://www.zoro.com/white-rodgers-dc-p ... lsrc=aw.ds


http://www.ebay.com/itm/WHITE-RODGERS-7 ... SwMgdX0t-3