1968 Pontiac Firebird Firewall Modification/Smoothing

Once again, it started out simple enough. I had removed the front subframe on the car to rebuild it (see separate page)
and stripped down the firewall for repainting. Over the years it seems like a lot of cars end up with a lot of holes in the
firewalls from all kinds of things like gauge installations or whatever. There were lots of these on my car. there was also
the big old firewall seam running right across the main visual center of the firewall. After having a look at lots of other
firewalls on the net and at some car shows I decided some minor smoothing could be done on my car. I had no intention
of getting rid of the factory "wrinkles" where the transmission tunnel started just the holes, spot weld dents,and seams.
I already needed to strip it to get the spray bombed black and undercoating off it anyways... so Off I go. Below are the
pics from my work on the firewall area. I was very pleased with the results and once again it ended up taking way longer
than I originally guessed it would.

Here is the engine bay before I started stripping all the sheet metal and frame off.

and once sheet metal was off...

and once the subframe was removed.

I made the body support out of some old castors. 4 little ones and 2 big ones and a bunch of scrap
metal. love my welder. the stand worked great and with the wheel dollies still on the back end I
could still slide the car around in the garage if i needed to.

the old blower box needed some refurbishing as well. I had installed a new heater core inside when
I did that box and I figured for the money and the difficulty of getting to it, I would put a new
blower motor on this end as well and reseal/caulk the box.

so off with the box and then start grinding away the old paint and raised edges.

and more grinding...

and one more of the grinding

then some filler after thorough cleaning with degreaser. I used my mig welder for filling some of
the holes. Of course I did not take any pictures of that. My first filler was some short hair
fibreglass filler because it is super strong. I was not sure about the heat in the engine compartment
expanding and contracting the area a lot so I used almost no regular filler. Just enough to fill
pinholes and final smoothing.

then after more cleaning and degreasing I sprayed 2 coats of primer. self-etching on the bare metal,
then primer sealer over everything. Sorry no gun on this, just good quality spray bombs.

of course after each coat of primer there are always some filling/sanding flaws that show themselves.
so That step took a long time until I was satisfied with the levelness and smoothness.Then, finally...
3 coats of Eastwood underhood black. which is a nice semigloss black.

then refinish the blower box. I sandblasted it first, then degreased it well. Then I coated it first
with a coat of the chassis saver urethane paint. you can see the brush strokes.

then 2 coats of the same underhood black from Eastwood.

put on the new motor with the freshly cleaned blower fan. Oh yeah, I sandblasted and coated the
inside of the box with Chassis Saver as well.

and the new motor side

new coat of 3M strip caulk around the sealing edges.

And it was done. Re-installed the heater box on the new smoothed firewall.


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