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Glue In Dual Exhaust Rear Floorpan Reinforcements
Floorpan Reinforcement: Install Classic Tube’s classic Mustang floorpan dual-exhaust reinforcements with or without a welder
Quite some time ago in Mustang Monthly we introduced you to Classic Tube’s dual-exhaust floorpan reinforcement panels for 1965-1970 Mustangs. These panels were factory installed in Mustangs ordered with dual-exhaust systems. Of course, the body assembly line crew spot-welded these panels in place, so they became an integral part of the vehicle platform.
If your Mustang came with a single-exhaust system from the factory, it will lack these reinforcement floor panels. However, if you’re planning to add a dual-exhaust system, you’re going to need some form of floor-panel reinforcement to accommodate the muffler and tailpipe hangers. Look to Classic Tube for these terrific reinforcement panels.
When we introduced these reinforcement panels to you, they were rosette welded (drill, plug, weld) to an existing floorpan at Classic Tube. Time passed, and it occurred to us that these reinforcement panels do not have to be welded if have no access to a welder or don’t want to risk fire in an assembled car. You can secure these pans with a good industrial-grade panel adhesive, or even silicone sealer or adhesive, and they will remain as secure as those that are welded.
You can install Classic Tube’s dual-exhaust reinforcement floor panels in about an hour, and we’ll show you the options. Exhaust hangers can be easily installed using stock mufflers. If you’re going with an aftermarket muffler, there are other options for exhaust hangers, and we’re going to show you that, too.
01. Here’s Classic Tube’s line-up of dual-exhaust reinforcement floor panels. From top to bottom, you see 1965-1966 with seatbelts, 1965-1966 without seatbelts, and 1967-1970 all. These are perfect-fit panels you can install in one to two hours with outstanding results. What’s more, you can use existing muffler bracket holes, or punch your own, depending upon what you do with your exhaust system.
02. A close look at the 1965-1966 panel with seatbelts: The large hole is the seatbelt anchor point. And remember, 1965-1966 panels are for 12/6 o’clock hanger brackets. From 1967-1970, the holes are diagonal.
03. The reinforcement panel is fitted into place, checked dimensionally, as shown, and locked down at the seatbelt anchor point. Once proper fit is established, drill the muffler bracket holes. No adhesive has been applied yet.
04. Pilot holes 1/8-inch are drilled first as a guide for the maximum size (1/2-inch) bit to come.
05. Apply industrial adhesive thickly across the contact surface. You may use silicone sealer (ideally, black), which has incredible bond strength once it cures.
06. The reinforcement panel has been permanently installed and secured with the seatbelt bolt and flat washers to achieve a solid seat. Alternatively, use sheet-metal screws to secure the panel until the adhesive cures. The exhaust system hanger stud package is now installed.
07. Classic Tube provides sheet-metal screws to secure the hanger stud bracket. You’re going to love this because you will never have to worry about your exhaust system falling off again—ever.
08. The left side installs the same way and is a mirror image the right. Secure the panel with the seatbelt bolt and large, flat washers. Drill the hanger bracket stud holes. We’re using a variable taper bit on the left side, which bores these holes out to size.
09. We have applied gobs of industrial adhesive on the left side and pressed the Classic Tube reinforcement panel into place. Once seated, it is secure and will never come out.
10. Classic Tube provides these factory-muffler compatible hangers, which are like original equipment. You can, however, modify these hangers anyway you wish to work with aftermarket mufflers. We tried this trick with spacers for use with aftermarket mufflers on a 1967 Mustang.
11. Here’s the Classic Tube exhaust hanger modified for use with aftermarket mufflers. Try to ignore the sloppy tailpipe welding. Our MIG welder decided to fail just as we were getting started. That’s our excuse, and we’re sticking to it!
12. You can eliminate the rubber insulator entirely and opt for a more rigid affair using the Classic Tube body bracket shown here. We’re taking this path to achieve tailpipe to floorpan clearance. Ford suggests minimum 3/4-inch clearance between pipe and floorpan.
Scott Drake Reproductions introduces these high-flow 1965-1966 Mustang exhaust tip trumpets that are sans louvers and available from National Parts Depot for installation on your classic Mustang. We like these tips for their clean-cut design, void of the traditional louvers you typically see on 1965-1966 Mustang GT exhaust tips. Without the louvers, these tips yield a cleaner sound, and with just the right aftermarket mufflers, deliver a bark you will long be remembered for.