We're working on a '66 Mustang restomod project that has been slowly creeping along for a decade. How does a project, begun in earnest, take so long? There have been challenges most of us can relate to, including a career change and other time consuming projects that had the Mustang spending time in a body shop collecting dust. When Virginia Classic Mustang sent us a pair of Flowmaster Series 50 Delta Flow mufflers to try out on this Mustang, it changed our attitude because we knew Flowmasters would give our floundering Mustang project that extra enthusiasm it needed to get to the finish line.
1 We're starting with Patriot...
1 We're starting with Patriot shorty ceramic-coated headers from the fine folks at PerTronix. Sergio's Muffler will take the Patriot collectors and enlarge them to work with our 2 1/4-inch pipes and mufflers.
The Series 50 Delta Flow is Flowmaster's ultimate street muffler. It delivers a deep, throaty burble at idle and that traditional Flowmaster sound without cabin resonance. It is important to note that Virginia Classic Mustang doesn't sell Flowmaster mufflers individually; they offer entire Flowmaster exhaust systems.
We've decided to go with a custom dual exhaust system because the car's owner, Gary Mattson, wanted unique exhaust tips instead of the traditional factory trumpets, which called for specialized exhaust fabrication work. We don't know where Gary sourced his tips, but they look terrific through the car's GT valance, although it was challenging to get these good-looking tips to fit both the tailpipes and valance at the same time.
Sergio's Muffler in Palmdale, California, did the pipe bending and installation for our custom dual exhaust project, which brings us to an important point. Search carefully for a muffler shop because good ones are hard to find. You want a muffler shop that's attentive to detail, and one that won't argue with you if you're not pleased with their work. We've learned this one the hard way in Los Angeles and suspect it's the same way across the country. Just about anyone with a welder and hydraulic pipe bender can hang up a shingle and call themselves a muffler shop, which is why you must shop reputation and word of mouth before putting your money down.
2 Virginia Classic Mustang...
2 Virginia Classic Mustang provided us with exhaust system hardware, including factory exhaust hangers. This makes for easy installation once the pipes are bent and welded together. We modified our hangers so they were adjustable for just about any kind of muffler. In this case, we're going with conventional clamps tied to modified hangers.
3 Sergio's Muffler enlarged...
3 Sergio's Muffler enlarged our Patriot collectors...
4 ...to fit 2 1/4-inch p...
4 ...to fit 2 1/4-inch pipe.
5 Like most muffler shops,...
5 Like most muffler shops, Sergio's Muffler uses wire to establish pipe path and bend.
6 We're doing the exhaust...
6 We're doing the exhaust pipes from the headers first.
7 Several trips back to the...
7 Several trips back to the Mustang were required to get the bends where we need them.
8 Both sides are bent to...
8 Both sides are bent to fit, then fitted for welding.
9 Once the exhaust pipes...
9 Once the exhaust pipes are fitted to the collectors, they're MIG-welded in place. Sergio's tack welds first to establish a solid fit, then welds a bead for 360 degrees.
10 When the entire exhaust...
10 When the entire exhaust system is installed, we will install a balance tube between both header pipes to create an H-pipe.
11 Both pipes are secure...
11 Both pipes are secure so we're ready to move on to the rest of Gary's custom-fabricated dual exhaust system.
12 Exhaust pipes back to...
12 Exhaust pipes back to the mufflers are bent and fitted next. The objective is to follow the same path as original, right down the driveline tunnel to keep pipes out of sight.
13 Our Flowmaster Series...
13 Our Flowmaster Series 50 Delta Flow mufflers are positioned for welding. There needs to be at least one inch of clearance between the mufflers and floorpan. Additional clearance is even better to allow for heat expansion and vibration.
14 Sergio's Muffler tack...
14 Sergio's Muffler tack welds first and checks fit before welding a solid bead full circle. It is a good idea to weld up an exhaust system even though it can be intimidating. Welding eliminates any chance of leakage.
15 Our Flowmaster Series...
15 Our Flowmaster Series 50 Delta Flow mufflers line right up with factory exhaust hangers from Virginia Classic Mustang.
16 The mufflers are properly...
16 The mufflers are properly positioned and checked for clearances all around before final welding. You want plenty of clearance from the driveshaft.
17 Tailpipes are always a...
17 Tailpipes are always a bear to fit in any application. Because Gary had unusual chrome tips, the tailpipes had to be custom fabricated by Sergio's Muffler.
18 Here's one of those chrome...
18 Here's one of those chrome tips. Sergio's Muffler had to enlarge the tip joint and carefully fit it to the custom tailpipe.
19 The left-hand tailpipe...
19 The left-hand tailpipe is bent, then checked for proper fit. Because the left side is extraordinarily tight, we found the tailpipe too close to the fuel tank.
20 Factory tailpipe clearance...
20 Factory tailpipe clearance is roughly 1-2 inches from the fuel tank. Our tailpipe wound up 1/4 inch from the fuel tank, which mandated custom bending with a side impression for proper clearance.
21 Sergio's Muffler carefully...
21 Sergio's Muffler carefully positioned the muffler and tailpipe, checking all clearances before welding everything in place. Because our tailpipes were a straight shot through Gary's valance, we could not use factory tailpipe hangers. Sergio's installed a pair of generic tailpipe hangers with modern rubber grommets.
22 Sergio's Muffler installs...
22 Sergio's Muffler installs a balance tube in order to join both sides. This improves exhaust scavenging and sound. When you don't use a balance tube, it gives your Mustang more of a popgun sound.