Lowered Floor Pans

Ok, how do you fit my 6'5" body into a car designed for the ideal height of 5'7"? Good question. Fortunately this is a question that lots of people a lot smarter than me have considered. Look around and you will find plenty of options to drop the floor pan down to give you more head room.

As I researched the options I found that there are two basic directions to consider. One is to just make a hole in the floor and weld in new pans to give you a place to bolt the seat directly to the floor - maximizing the amount of drop and headroom. A great option is you have standard seats and don't care if you ever have any seat adjustment options. This wasn't the best option for me.

The second option I found was to tilt the back of the floor pan down about 3" so that additional headroom is gained while maintaining the option of seat adjustment. I found quite a bit of good advice on the DeTomaso Pantera Community website - specifically at this post.

http://pantera.infopop.cc/eve/forums/a/tpc/f/6450045562/m/428106782/p/4

Here a gentlemen by the name of Kirk Evans shows a step by step procedure how to drop the pans, angle them back and weld it all back together to give a nice option for gaining more headroom. I believe this option will work with about any seat you use that would normally fit the Pantera. I decided this is how I would modify 3854.

With the website opened on my cell phone, I decided to tackle taking out the driver's side floor pan first. As I laid out the cut on my pan, I decided to modify what I would remove slightly to give me more side to side room for the seats I had purchased for my project (see separate post). In the following picture you can just make out the lines I scribed into the paint of the floor pan showing the approximate position the Evans method outlined in the post mentioned above. By the way the front of the car is facing to the left in this photo - again, this is the driver's side pan.

To make the hole wider I decided to go to the very edge of the pan welds, where the metal doubles over next to the center console and the door jamb. This gave me about 1" more hole width - space I could seriously use. The length of the cut from the doubled piece of metal at the fire wall to the front of the car was 24 3/8 inches. You can see the line scribed in the pan to the left side of the picture above.

After a bunch of double checking it was time to start the cut off wheel. I covered as much of the dash and center console as possible so as to not cause spark damage. The cutting process was pretty simple. There are several places where you will cut into or around support under the car. Kind of a scary process but it works out just fine.

On the left side of the picture above you are cutting into the cross member support that runs from side to side of the car. This is an area you will spend a lot of time welding up a new cross member that should actually provide more support and rigidity that the original design. By cutting no more than 24 3/8" from the back of the car to the front you leave just enough of a lip to give a good welding surface from the remaining floor pan to the new support you will add.

You will have to get under the car and cut into this cross member (the part towards the back of the car) leaving enough metal there to hold your new cross piece. Take a look at the picture below showing what was left after removing the pan.

Unfortunately the sun helps mask what is left on the front of the floor but if you look closely you will see how I ended up cutting the floor pan free. I also cut the rear support just in front of the hole in the upper right side of the picture straight down from the floor. I think the Evans method has you cutting this support at an angle - I decided to cut it straight to give me more options - I will box it in later to add back the rigidity.

This next picture shows the cross member being laid out.

I used a piece of 1x3 box tubing that I had from another project. It isn't particularly heavy but will be very strong once welded into position. You can see how I cut the floor pan and the cross member (the rusted piece below the tubing). By cutting it this way I can weld the top part of the floor to the tubing then take a hammer and pound the cross member up to the 1" side of the tubing and weld it together. This basically takes the cross member and makes it the size of the 1x3 tubing. Very strong!

I cut the 1x3 31" long so as to slide through the cross member under the console support into the cavity under the passenger side floor pan. When I drop that side of the pan I will weld together more 1X3 on that side basically making the cross member one continuous piece. Unfortunately the geometry of the holes opened by the cutting of the floor pan won't allow one piece of tubing to be inserted. You will have to cut it down and reweld it back together after it is placed.

The 31" piece I used also had to be cut in half to get it inserted properly. The piece that goes under the console support had to be notched to make room for the coolant pipes and the vacuum pipe that runs the length of the car. Here's a picture showing the beginning of the welding process.

You can see next to the clamp at the top of the picture where I welded the two pieces of tubing back together after inserting the one piece under the center console support. You can also see the weld at the top left of the picture where the floor is being welded to the tubing. I inserted thin metal into the gap that resulted from the difference in height between the 1x3 and the remaining floor to give me a decent place to weld to. filled all other gaps with appropriate sizes of triangle pieces of metal and boxed in almost everywhere left opened by all the cutting I did. 

The last weld I did was to join the bottom of the original cross member with the 1x3. I beat the bottom part of the metal I left on the cross member up around the back side of the 1x3 and welded the two pieces together 

Here's some pictures showing the finished cross member welds.

The bottom weld in the picture below shows where I welded the 1x3 to the remianing metal left on the bottom of the cross member cut. All gaps were welded with cut metal to box in allow openings. This gives you a good strong support. Some smoothing of welds will be required but not much since most of the weld will be hidden by the new floor pan.

The openings in the picture below will be closed by the new floor pan. I decided not to box these in yet since they will interfere with the fit of the pan I will be adding later.

Next I used 13 gauge sheet steel to make the floor pans. This is definitely over kill in the size but I wanted the pans to be very rigid. I first started by cutting and welding up the piece that will be at the back of the floor. This is what gives me the drop I wanted. I decided that 3" is what I'm going to live with. 

I cut a piece of sheet the length of the opening and cut it 4.5" wide. I wanted the extra 1.5" to be a support for the floor pan itself. I bent this piece at the 1.5" mark so that floor would be 3" dropped at the back of the pan. 

The 90 degree bend isn't exactly the angle that I will need to mate up to the floor pan. I will bend it up to match the pan when the pan is welded in place. This design will help hold the pan in place and give two good welding surfaces to secure it into place. I also welded the original support that I cut when removing the plan to this new piece added to the Pantera. 

Next came the pan itself.  I simply measured the opening that was cut and added 1/4" for the bends that I wanted to add to shape the pan into place. I ended up cutting most of the 1/4" away to make it fit properly. This shot show the pan welded into place.

This is the only place I ended up giving the pan a bend. I wanted the floor new pan to blend in with the original pan so I gave it s slight bend to match up to the 1x3" cross member added earlier. This really gave it a good fit and look. 

Here's a shot under the car showing the lip that I bent up to meet the pan. With the pan welded on the top side it was easy to use a hammer to shape the bottom lit to match pan easily. This really gave the pan a solid feel.

Then it was just a matter of making the side pieces and welding them up. I used a piece of cardboard to cut the shape needed to fit perfectly and cut out the sheet using the template. Here's a shot of the one side welded up. 

A bunch of welding wire later it's done. I have to say I like how it all came out. 

Unfortunately nothing can mask the fact that the pan was dropped. Here's a shot from under the car. 

Best part is that I sat in the floor and WOW what headroom. I really like how this all came out and am looking forward to mounting the seat rails and seeing how the seat actually fits the new pan. Now onto the passenger side. 

Here's the passenger side completed. 

The biggest challenge was to get the e-brake bracket boxed in. I sat the new seat into the hole and found that I will need to do a little trimming on the door side of the side rail. The dial that lays adjusts the seat back interferes here. I think by taking away some metal near the hole that is already there will fix this problem completely. Here's how I decided to box in the e-brake support. 

Later I will prime and paint the entire surface. The next step is to install the seat rails. That will be in a separate post.