Muscle Car Restorations (MCR)

Restoration Articles

Metal Work - Mini Tubs - 65 Belvedere

Added August 2007

How-to, Tutorial, Step-by-step, Technical Article

Should I restore it totally stock or build it for performance? How about if I modify the drive train but leave the body stock? What changes can be undone if I want to make it stock again? What modifications will help or hurt the value of my car? How much will the performance be limited by staying stock?

Without a doubt, there can be a lot of options to be considered before a restoration project gets under way but they are really not difficult decisions once you know what you want your dream to look like. Our experienced team of professionals will keep you out of trouble.

A common request we get, for instance, is from someone who wants to build the street machine that they didn’t have the time or money to do they were younger. You know what we are talking about. A modified drive train and the perfect set of wheels and tires and an awesome eye catching paint job on the stock sheet metal. Unfortunately, all to often, the back end had to be jacked up to get a decent set of tires under the rear. It was that or tub the car.

Today, with the value of some of these cars, we find that we are more often removing tubs than installing them. But we still need to find room to get some good sized rubber in rear wheel wells. What we believe to be the ideal solution are mini tubs.

What we do is expand the inner wheel wells as much as the frame rails will allow by sectioning the rear of the floor and the trunk floor and splitting the wheel wells in two and filling the gap with new metal. You gain two to three inches of width and keep the stock rearend and suspension. Best of all, the car looks completely stock to everyone but an expert looking in your trunk and you can finally put some adequate tires out back that will hold up under the 500 HP you plan to put under the hood. Also, this is the type of modification that won’t hurt the overall value of the car and some might even argue that it’s a plus.

Here’s how we did it on a recent project. The car is a 65 Plymouth Belvedere but most others are similar. We think this is an especially good idea if you have to replace the wheel wells anyway as you are almost half way there to start with.

With the wheel wells removed, start by marking out the exact location of your cuts. You must be sure to keep everything in line with the frame rails. You want to move the lip on the edge of the floor so it is flush with the frame rail. The metal between the two lines is what will be removed.

Cut along the inside line first and move the lip in and tack it in place. When you are satisfied with the new position, make a cut through both pieces along the inside line. Peel back the section you are removing and tack weld as you go. Notice that we cut out the corner of the sectioned piece so we could save the factory stamped hole. This is our standard procedure for joining two pieces of sheet metal. If you are not familiar with this, please see the other tech article we have on our site that details this process.

Obviously, you need to do this for both the passenger floor and the trunk floor. These photos show the amount of extra room that we gained.

Of course moving the floor lip inboard requires that we form a new piece to fill in the gap.

Next, cut the wheel well in half and mock up the inner half to be sure that everything is fitting correctly. Now is the time to make any adjustments that might be necessary.

Now you can mock up the outer half to the fender lip, measure the gap and cut a filler piece. Using more then one piece is fine if that make it easier for you. We generally use two just because our sheet metal shear is limited to four-foot cuts. Tack the filler piece in numerous places and double check that everything is fitting correctly.

As you can see, this procedure is really not all that complicated. And you can probably already see that it’s going to be hard to tell that this wheel well has been modified.

Again, use our standard method for sheet metal welding to finish joining the two halves of the wheel well and all the other seams in the floor. You may have noticed that we also had to modify the trunk hinge extension bracket as it used to attach to the side of the wheel well but now it will be on top of it. The gain in this case was a little over 2 ½ inches. That’s enough to fit a significantly bigger tire without affecting the stock look of the car.

What Next?

- Questions, comments, article ideas? Let us know!

- Check out the other restoration articles available here at the tech section of!

- View our 35,000+ photo online restoration gallery.

© 2015 Muscle Car Restorations - All rights reserved