Rear Firewall

[FFRSpec72]

So looking at putting in a rear firewall, looks like it may be better to have the firewall attach from inside the fuel tank area and not from the engine area, as if I need to access the front of the engine I have to be inside the car anyway. I was only going to use 1/8 aluminum, not sure 1/16 steel would be better. I was going to divide this up into 3 triangles with 1 hole for the wiring and the ECU will attach to this firewall. So to access engine I can remove seats, cockpit firewall and fuel cell, not the best but accessible. Thoughts?

28226

[Bob_n_Cincy]

Tony
I used 0.090 aluminum on my ECU box.
I chose the aluminum to stay the same as the rest of the car.
I thought 0.090 was a good thickness for strength fire stop.
I will use a ~10" x 50" rectangle on the bottom and 3 triangles on top.
Bob


28217

[svanlare]

Bob,
What did you use for connectors through the firewall?

[FFRSpec72]

Tony
I used 0.090 aluminum on my ECU box.


Bob, looks like you attach from the engine side, any major reason for that and not attaching from the fuel tank side ?

[Bob_n_Cincy]

Bob,
What did you use for connectors through the firewall?


28219

I used a breather elbow off a 97 Mercedes.
I split them, put them over the wires, and pressure fit them in holes in my panel.
http://www.carpartsdiscount.com/pcv-valve-system-breather-hose-elbow.html?3593=60047



Bob, looks like you attach from the engine side, any major reason for that and not attaching from the fuel tank side ?
I am going to add another triangle on the cockpit side of the frame to waterproof the ECU in it.
Bob

Edit: Tony, in your case, I would want air space between the firewall and gas tank to prevent heat transfer.

[svanlare]

Bob,
Thanks for sharing, the solution looks very clean.

Tony,
watching with interest, as I'll be building something like this too before the engine goes in.