1956 Chevy Bel Air Floorpan - Super Chevy Magazine

When resurrecting a vintage car, it's important to have a well thought out game plan. A thorough examination of the car from top to bottom will determine its needs and help determine just where to get started. In the case of Steve McDonough's '56, which you saw in our 2008 issue of Chevy Classics, it was rescued from its past life as a poorly constructed '80s-era Pro Street car and given a chance for a rebirth into the Pro Touring world.

With the talented team at Competition Specialties in Walpole, Massachusetts, having completed the installation of a new trunk and stretched wheelwells, it was time to concentrate on the installation of a new one-piece steel floorpan from Harmon's. The new pan from Harmon's is constructed from heavy weight steel and is the perfect piece to tie the car back together to regain its original rock-solid feel.

The team at Competition Specialties laid the new one-piece floorpan from Harmon's on top of the Art Morrison Tri-Five GT Sport Pro Touring chassis to get a rough idea of how everything will fit before installing the pan to the body.

The team at Competition Specialties laid the new one-piece floorpan from Harmon's on top o

Separating a car from its chassis is a major undertaking. Peter Newell and his team at Competition Specialties are veterans at this type of surgery and we followed along as they began the process. In preparing to drop the chassis, the team began by draining and disconnecting all fluid lines, including those for cooling and heating, fuel, braking, and transmission. From there it was on to wiring, making sure harnesses for the engine and lighting were all disconnected, as well as the ground straps and battery cables.

Moving on, the team then addressed the steering column, throttle, emergency brake, speedometer cable, and shift linkage. The final steps included removing the front and rear bumpers, front wheelhouse lower splash pans, and breaking free the body mount bolts from the chassis. Once steps were completed and with all team members keeping a watchful eye at each corner of the car, the body was removed from the chassis using a lift. After separation, the tired old Pro Street chassis was rolled out and the team began evaluating the removal of the original floorpan.

1956 Chevy Bel Air Floorpan New Floorpan

This close-up of the top of the pan lets you see just how nice it really is. Made from heavy gauge steel, it features welded in braces, embossed floorpans, and the quality that Harmon's has become known for.

This close-up of the top of the pan lets you see just how nice it really is. Made from hea

Peter used a bright yellow Markal B paint stick to create a visual path to follow once the Sawzall got fired up. Before starting, it was important that both the floorpan and the body were securely braced while on the lift. This would eliminate any potential accident, or flexing of the body when the support structure was taken away during the procedure. Once pilot holes were drilled to allow access for the Sawzall blade to enter the seams along the pan, the initial cutting went without a hitch.

To then remove the central pan, team members were at each corner to eliminate the support braces and lower it to the ground. Seeing that the new Harmon's pan incorporates fresh bracing and inner rockers, the removal of these areas from the original pan were then addressed. Cleaning up the mounting areas for the new pan was a snap using a disc grinder topped with an 80-grit wheel.

To test fit the pan, Peter first placed it on the new Art Morrison Tri-Five GT Sport Pro-Touring chassis shod with massive P345/25ZR20 rear tires mounted to Boze Fatal wheels. This showed that a bit of trimming would be needed in order for the combination to work. Peter carefully measured and removed 3 inches from each side of the rear of the pan, which would later be reworked and welded in again to give the area a factory-like look. With the trimming completed, the team clamped the pan to the body and lowered the body onto the new rolling chassis to ensure everything would line up perfectly, including the body to chassis mounting points.

With the interior, carpet, and insulation removed, you can see that the car's original pan has suffered through its share of surgeries over the decades.
With the interior, carpet, and insulation removed, you can see that the car's original pan
Looking to the rear of the pan, the horror became more evident from an '80s-era backyard tub job.
Looking to the rear of the pan, the horror became more evident from an '80s-era backyard t
In preparation for dropping the original chassis from the car, it's a good idea to start a day ahead by giving the body mount bolts a good soaking with a rust penetrating agent like PB Blaster Penetrating Catalyst.
In preparation for dropping the original chassis from the car, it's a good idea to start a

With the body mount bolts broken free, their removal would be a breeze once the remainder of the car was prepped for separation.
With the body mount bolts broken free, their removal would be a breeze once the remainder
A portion of the preparation for dropping the chassis had Peter Newell (left) and Brian Jordan (right) draining and removing the fuel cell from the original chassis.
A portion of the preparation for dropping the chassis had Peter Newell (left) and Brian Jo
Working diligently under the car, Peter removed the bottom fender bolts. There is a large laundry list of items that need to be addressed before the final separation of the chassis from the body takes place.
Working diligently under the car, Peter removed the bottom fender bolts. There is a large

With the green light given regarding the fit, the team separated the pan from the body one last time to pre-punch 3/16-inch holes for all spot welding points. With all metal-to-metal points ground clean with an 80-grit disc to ensure a proper welding base, the pan was secured to the body using a Lincoln Electric MIG welder. After all welding had been completed, a pass with a disc grinder cleaned up the welds and brought the job to completion. In final form, the new floorpan not only looked great, it gave the car's structure plenty of added strength and prepared it for future infusions of horsepower once the project hits the streets.

Having the original chassis out of the way, Peter marked the floor seams to be cut with a Markal B paint stick, thus laying the course for the initial rough cuts to be made. Once a pilot hole was drilled, he followed with a DeWalt Sawzall to make the incisions. Note the pan has been properly supported for safety during this process.
Having the original chassis out of the way, Peter marked the floor seams to be cut with a
The sides of the floor were marked to outline the areas that need to be addressed by the Sawzall.
The sides of the floor were marked to outline the areas that need to be addressed by the S
Paul Thetonia used an air chisel to break into the outer seams of the floorpan and prepare it for the Sawzall. Always be sure to wear safety glasses!
Paul Thetonia used an air chisel to break into the outer seams of the floorpan and prepare

With the floorpan properly braced for support and team members close by, Paul proceeded to work his way down the side of the pan with his Sawzall, paying close attention since he had to work his way around the factory floor braces.
With the floorpan properly braced for support and team members close by, Paul proceeded to
Coming to the front of the floorpan, Paul went to work with his air chisel to continue along his marked path cutting through the transmission tunnel area.
Coming to the front of the floorpan, Paul went to work with his air chisel to continue alo
There's nothing like a pile of nasty old metal to help you appreciate the complete new floorpan from Harmon's awaiting installation.
There's nothing like a pile of nasty old metal to help you appreciate the complete new flo

Once the original pan was gone, removing the balance of the inner rockers as well as any remaining support braces was a snap. The new section from Harmon's incorporates all new bracing and inner rockers making it a nice complete unit.
Once the original pan was gone, removing the balance of the inner rockers as well as any r
Using an air chisel, Brian continued the removal of the inner rockers following all of the original spot welds.
Using an air chisel, Brian continued the removal of the inner rockers following all of the
Using a disc grinder topped with an 80-grit disc, Brian cleaned up any remaining debris to prepare the area for the installation of the new floorpan.
Using a disc grinder topped with an 80-grit disc, Brian cleaned up any remaining debris to

Once all of the original inner rockers and bracing were removed, all that was left was a bit of straightening to ready the area for the next step.
Once all of the original inner rockers and bracing were removed, all that was left was a b
Continuing to the front of the car, Brian used his Sawzall to first remove...
...any remaining bracing followed by his disc grinder to clean up any stray metal issues.

Following all of the original spot welds during the removal process should ensure that the new pan installation will go smoothly.
Following all of the original spot welds during the removal process should ensure that the
Peter made sure that any exposed internal sheetmetal areas were treated to a nice even coating of Rustoleum gloss black for added protection against corrosion.
Peter made sure that any exposed internal sheetmetal areas were treated to a nice even coa
In order to determine the approximate amount of trimming needed to the Harmon's floorpan due to the upgraded wheel and tire combination, Peter...
In order to determine the approximate amount of trimming needed to the Harmon's floorpan d

...laid it on top of the Art Morrison Tri-Five GT Sport Pro Touring chassis. He concluded that 3 inches (marked here) would have to...
...laid it on top of the Art Morrison Tri-Five GT Sport Pro Touring chassis. He concluded
...be removed from each side to allow ample clearance for the new rollers. The section removed will later be reused for the final fit of the pan to the body.
...be removed from each side to allow ample clearance for the new rollers. The section rem
Having completed any needed trimming of the pan, it was then clamped into place. This was also a perfect time to make sure everything lined up correctly, including lowering the car down onto the new chassis to check for proper fit to the body mounts.
Having completed any needed trimming of the pan, it was then clamped into place. This was

Brian pulled the pan down one last time and using an air-driven hole-punch, added a number of 3/16-inch holes to spot weld through.
Brian pulled the pan down one last time and using an air-driven hole-punch, added a number
After all adjoining metal areas to be welded were ground clean with an 80-grit small disc grinder, and with everything lined up for the final time, Peter used his Lincoln Electric MIG welder to spot weld the pan into place.
After all adjoining metal areas to be welded were ground clean with an 80-grit small disc
After all of the spot welding was completed, Brian used an 80-grit disc on his grinder to clean up all of the welds, thus giving the area a clean, finished look.
After all of the spot welding was completed, Brian used an 80-grit disc on his grinder to

Inside the car, the floorpan was secured to the new trunk pan to prepare it for welding using clamps and sheetmetal screws.
Inside the car, the floorpan was secured to the new trunk pan to prepare it for welding us
Peter completed all of the final MIG welding inside the car and followed with a grinding disc to complete the job.
Peter completed all of the final MIG welding inside the car and followed with a grinding d
The interior of the...