TECH SMOOTH OPERATION
The factory firewall has a lot of unnec-
essary holes for modern builds that take
builders time to patch and weld up to
achieve the desired look. In addition,
the factory firewall recess presents
fitment issues for LS and LT series
engines, similar to those encountered
with big-block installs in the past.
Cofounder of Real Deal Steel and
longtime Tri-Five expert Joe Whittaker
explains how these things came
together. “The firewall was alreadyavailable from Hot Rod Dynamics
(HRD) and we began offering it because
our customers wanted an attractive
custom firewall. For years, customers
have asked increasingly for a custom
transmission tunnel to accommodate
the larger late-model GM automatic
and manual transmissions common
with LS swaps. We asked Joe Lutz from
HRD to work with us on designing a
piece we could insert with minimal fuss
that would expand the factory tunneland work with the recessed firewall
piece. After three years of test-fitting
and fine-tuning, he finally got all the
dimensions figured out to give custom-
ers what they wanted.”
The new pieces are made from
16-gauge steel to properly match up
with the existing body panels. The
recessed firewall is a modern affair and
not compatible with the factory heater
box or wiper motor. This is not really
an issue, though, since most people
ditch the factory pieces anyway for a
modern wiper setup like those available
from Raingear and aftermarket climate
systems like those from companies like
Vintage Air.
The new firewall gives 4.125 inches
of uniform firewall recess depth, allow-
ing for easy fitment of LS/LT engines
with the coil packs mounted on the
valve covers and more clearance for
exhaust headers. It also allows for build-
ers to set the engine back farther in the
engine compartment for more clear-
ance between the engine and radiator,
and improve the car’s weight distribu-
tion. The transmission tunnel insert
eliminates all the previous clearance
issues for late-model automatics (and
manuals) so the drivetrain can be set in
place without having to break out the
hammers and pound on sheetmetal.
Customers ordering a new RDS
Tri-Five body can have these pieces
installed at the factory (as we did with
our new ’55 project) or they can be pur-
chased separately by anyone working
on an original body that wants to make
the same modifications. Having these
pieces installed by RDS when building
the body is far cheaper than having a
shop install the parts later on.The factory Tri-Five firewall, in this case
a reproduction from Golden Star Classic
Auto Parts, was well designed for its day,
but the modern world presents issues on
both the functional and aesthetic fronts.
Today, builders want a clean firewall that
is uniform and easy to work with. Many
of the factory holes aren’t necessary
with aftermarket upgrades, as well.1