Firewall Reconstructive Surgery

By: Don Emmons
   At last, there's help for abused Ford F-100 firewalls. Whether you're restoring or street-rodding an F-100, the firewall on those 40-plus-year- old trucks are sure to be punched full of holes. The current trend includes filling in all holes on the firewall to give the engine compartment a totally smooth look, matching that of the exterior. Now, there is help. The Mid Fifty Company produces new firewall sheetmetal for F-100 trucks. Long ago, Ford Motor Company ceased offering replacement pieces through its parts counters, leaving enthusiast no choice but to weld up their butchered trucks. It rust was more prevalent than metal, you had to go looking for another cab to cut out the section of firewall and then patch it in.    Mid Fifty came to the rescue with a new stamping that is free of even the stock holes so you can select the pieces needed for a totally smooth wall for a really custom look. The company invested in a set of new dies, which allows them to stamp out the firewall in a two-piece unit. Firewall halves are sold separately, allowing replacement of only part of the wall as needed.    Installing the new pieces requires that the old unit be removed by drilling out the factory spot-welds. If the area is still original, it will be easy to see the spot-welds. Drill them out using a ¼ inch drill bit. That will not be a problem because after setting the new pieces into place, simply plug-weld the holes and it's back to stock appearance. If plans include the ultra-smooth look, simply grind everything down, add some filler, and do a lot of sanding.    Recently, we stopped by Bobco and followed along as the staff installed one of the units. The truck was undergoing total reconstruction with a complete smooth look, so we decided to give our readers a look at the entire redo. If you're planning to take the project back to original, drill holes as needed for your setup. Bobco can supply a set of this sheetmetal and install if it you are not inclined to tackle the job. It does require good welding skills and the proper equipment - or the sheetmetal can be mail-ordered and a local body shop can perform the installation for you. The good news is that there are new pieces to start with at last.
  1. If the firewall on your truck looks something like this, you probably will be very interested in this article. We visited Bobco and found the staff in the process of replacing a very badly abused firewall with a new unit from Mid-Fifty.

2. With a bit of time and a lot of work, your firewall can look as pristine as this one. This is the easiest way to get a totally smooth look since the new firewall comes without any holes, even the stock holes. Simply weld it in and grind it down for a great-looking firewall.
3. Here's a look at the new Mid Fifty '56 Ford F-100 firewall. It comes in tow pieces and must be welded up after the two halves have been installed into the truck. That means that half a section can be purchased if that's all you need.

4. Start by grinding off all of the old paint so that all of the spot-welds are visible. Drill out all of the old spot-welds so the old unit can be removed without damaging the surrounding area.
5. An easy way to remove the old firewall is to drill out all of the spot-welds that hold it in place. A ¼ inch drill bit works well to remove the entire weld area and free up the back piece. Use a screwdriver to help separate the two as you drill. Some welds might require the use of a flat chisel to break the two loose. Repeat the procedure along the bottom of the firewall where it is welded to the floor panel.

6. New firewall panels come painted for protection and must have the paint ground off on the areas that are to be welded.
7. Flange the passenger side so when the driver side is placed over it, the front surface is flat across the unit.

8. It is difficult to run the flanging tool along the entire length of the pieces due to the contours of the metal but it must be done for an overall smooth finish.
9. Make sure that the paint has been ground off completely around the whole outside area for a good, clean surface for welding.

10. Don't for get to clean off the paint from the back of the driver side where it overlaps the other piece.
11. After all top and bottom areas of the body have been ground down to bare metal, set the passenger side into place and clap it down. Do not skimp on clamps.

12. Start on the top to work the panel into place and work down the side and across the floor panel. Double-check all around the piece to make sure everything fits properly. If necessary, go back and make adjustments.

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