Flowmaster U-Fit Exhaust Kit Install - DIY Exhaust Pipes

1 Here is the 2.25-inch U-Fit kit from Flowmaster. It's made from mandrel-bent, 16-gauge aluminized steel tubing and comes with all the necessary bends and angles you need to do the job at home. You will need to pick up a set of mufflers, a hanger kit, and possibly some tips to round out the system. Some of the sections of pipe have an end that has a larger diameter. This is so you can slip it over another piece of pipe for easy install.

1 Here is the 2.25-inch U-Fit kit from Flowmaster. It's made from mandrel-bent, 16-gauge

In the past couple of issues, we have shown how to build some pretty exotic headers and exhaust systems. We thought we might be missing a segment of do-it-yourselfers who are not ready to build a custom set of headers, but can definitely tackle welding up some pipes. In this issue we put the finishing touches on a mild V-8 swap into a ’63 Nova wagon. We used as many bolt-ons as we could, but when we got to the exhaust we just couldn’t find a bolt-on kit. Luckily, there are a few builder-type set-ups available, like the U-Fit exhaust kit from Flowmaster.

The U-Fit kits are available in 16-gauge aluminized or stainless steel in 2.25-, 2.5-, and 3-inch diameters. The U-Fit kits include the front adapter pipes, intermediate pipes, H-pipe assembly, over-the-axle pipes, and your choice of optional tailpipe exits. Each piece has a slip-fit connection to ease assembly. The kit doesn’t include some of the things you’ll need to build a complete system, like mufflers and hangers.

2 When it comes to the mufflers, there are many options to choose from in the Flowmaster line. Josh says "You want to look at the muffler's overall dimensions and check that against the space you have available under the car." This shot shows the difference in size between the 50 series (bottom) and the 40 series. The 50s are quieter, but are too big to fit without dropping them closer to the ground. We wanted a more agressive sound anyway, so we used the 40 series and also kept our ground clearance.

2 When it comes to the mufflers, there are many options to choose from in the Flowmaster

For this early Nova’s 290-horse small-block crate engine, Flowmaster recommended the 2.25-inch system. This is plenty for the mild Mouse, but just as important, it gives us a bit more clearance for the steering area, which is pretty tight on this generation Nova with headers.

We wanted this car to have that "Flowmaster sound" so we grabbed a set of the company’s 40 Series two-chamber mufflers. The 40 Series muffler delivers an aggressive exterior and interior tone. It is constructed of 16-gauge aluminized steel and fully MIG-welded. There are quieter options in the Flowmaster arsenal, but we are still into that aggressive exhaust sound so we stuck with the 40s.

3 Josh tells us the first step is to do a quick lay out on the floor so you will know what pipes go where. Each pipe has a certain place it wants to be, but you can also change them up depending on your particular needs. There are a few pipes that are used for a specific spot, like the 90-degree bends that are used at the head pipes (in front of the muffler) and the two that come together to create the over-the-axle section (behind the muffler).

3 Josh tells us the first step is to do a quick lay out on the floor so you will know wha

Since it would be really difficult to shoot the pictures and do the work, we hooked up with Josh Gledhill, owner of The Muffler Man in Placentia, California, to install the system. Enlisting the help of a professional was the smart thing in our case--not that this is a super difficult job to do, but our welding skills leave a lot to be desired. Not only can Josh lay an awesome bead, he also clued us in on a bunch of tips that we’ll pass along to you.