Auto enthusiasts understand there are any number of reasons for an aftermarket, or OE replacement exhaust system not fitting. Everything from the displacement of hangers on either the car or pipes, to unexpected contours or dimples in the floorboard can present a host of fit problems. And the possibility of being drawn into hours of cutting, welding, and clearancing to finally get a satisfactory fit may not be worth the cost or the effort.

Using flexible steel tubing to join misaligned sections of rigid exhaust tubing is the perfect solution for a host of exhaust system headaches – particularly ones that require more than just minor alignments. No other approach resolves underside fit and emissions compliance issues more efficiently, while still preserving the vital vacuum seal needed for exhaust scavenging.

Flexible Tubes Are the Ideal Solution for Exhaust System Sealing 

Let’s be honest: no matter how much a car or truck owner invests in a new exhaust system, there’s no guarantee that it’s going to fit perfectly. Fortunately, high quality universal fitting flexible exhaust tubing is available to cover and seal the gaps and spaces between improperly fitted pipes. 

While some specially-designed graphite exhaust gaskets are capable of closing bigger than normal gaps, they’re ineffective for spaces larger than a few centimetres, for major misalignments, or for tubes whose flanges are warped. Flexible tubes, however, are designed to slide over bent or misaligned exhaust tubes, and are manufactured with attributes that include:

• Strip-wound 304 Grade stainless steel construction that’s corrosion and pressure resistant;
• A smooth, leak-proof inner liner with heat resistance to 600°C; and,
• A 2.5mm nominal thickness, with interior diameter sizes that range from 25mm – 152mm.

Once cut to the required length and slipped into position, flexible exhaust tubes form a strong, leakproof seal that directly connects the gapped sections without cutting or applying heat to either the exhaust system or the vehicle’s underbody. And given their wide range of interior diameters, they’re the perfect solution for virtually any car or ute exhaust systems, as well as the large diameter systems found on prime movers, power generators and agricultural equipment.

Flexible Exhaust Tubes Simplify Low Pressure Gas Management 

While closing the space between misaligned and warped exhaust segments is what flexible exhaust tubes are most commonly associated with, there are a host of other-than-ordinary exhaust jobs that they’re equally well matched for. This is especially true for exhaust system reconstruction and design activities, including:

• Performing urgent patchwork repairs to cracked or rusted exhaust systems;
• Making tentative fixes to exhaust systems damaged while off roading; and,
• Routing ADR-compliant catted exhausts equipped with custom side dumps.

In each of these cases, especially when it’s necessary to mend an already mounted system, flexible exhaust tubing’s dependability qualifies it as a must-carry item anytime an owner is contemplating a long journey, or a harsh off-roading session. And the same level of reliability that makes them perfect for on-the-road exhaust repairs also extends to their ability to take on a wide range of intake system and other low pressure gas management chores, including:

• Setting up, fixing and repairing underbody fresh air ducting;
• Sealing heat resistant underbonnet plumbing for air snorkels; and,
• Creating mock-ups for custom cool air intake and exhaust systems.

When correctly sized and installed, durable flexible steel tubes are as effective as rigid exhaust tubes at minimising exhaust noise and emissions. And their ability to tie unconnected sections of solid tubing together is critical for reducing stresses and vibrations that could ultimately compromise the entire system. They still require a means of joining and sealing that’s as reliable as tubing itself, though. That’s where a wide variety of both high strength mechanical and chemical fasteners comes into play.

Choosing the Right Fastener For the Best Flexible Tubing Seal 

With the main advantage of flexible exhaust tubing being its light weight and workability, it’s only natural that achieving a good seal should be just as straightforward. And while welding and other types of flame-based joining processes are the most likely sealing choices, they’re not the only options.

Along with welding, there’s a solid array of heat resistant products on the market made especially for sealing exhaust systems. And with the right tools, drivers can often make their own emergency repairs without raising the ire of local traffic enforcement.

• High heat welding. Regardless of whether it’s MIG or TIG, welding is the most time-tested method of joining flexible tubing. However, applying heat to the thin steel walls of flexible tubes without burning through can actually problematic for less experienced welders.
• Standard exhaust clamps and wraps. Every driver should have exhaust clamps in their toolkit. But when used to hold high temperature woven exhaust wraps in place, they’re capable of producing reliable, vacuum-tight exhaust seals that can be trusted not to leak.
• Ceramic-based exhaust sealants. Iron-reinforced, ceramic-based exhaust sealants are designed especially for the high temperature environments of exhaust systems, and are regularly used to repair exhaust tubes and mufflers, as well as collectors and extractors.
• Titanium exhaust tape. Metallic exhaust tapes are designed especially for high temperature forced-induction environments, offer 1200°C continuously rated protection once they’ve been set, and are perfect for sealing leaks and gaps.
• Extreme temperature silicone sealants. Thermally stable, extreme temperature RTV (Room Temperature Vulcanising) silicones are flexible yet durable, and aren’t prone to cracking due to heat cycling when used on exhaust systems.

It’s important to remember that when it comes to sealing exhaust systems, there’s more at stake than just keeping noise and emissions under control. A good exhaust seal is essential for good scavenging, and ultimately for good combustion. That means together with opting to use flexible tubing, choosing an efficient fastening method is a critical aspect of engine performance.

The Final Word

At the end of the day, regardless of whether it’s the result of an off-spec aftermarket component, or a warped flange from an underside strike, a misfitting exhaust system needs to be connected and sealed as quickly as possible. A ruptured exhaust tube becoming dislodged on the roadway can be catastrophic, which makes having a way to safely reconnect the two sections can be a lifesaver.

Universal fitting exhaust tubing is the perfect solution for ruptured, or misaligned rigid exhaust tubing. It’s the most reliable and economical way of resolving a potentially costly exhaust problem.