2.5 in Exhaust Tubing Bend Kit ZTL-25RAW-8P - DIY Mandrel Bend

In this review the ZTL-25RAW-8P kit is judged as a practical, no-nonsense exhaust tubing set for DIY fabricators who need a complete selection of mandrel-bent pipes. The biggest reason to buy is its combination of 18-gauge mild steel with computerized mandrel bends, which gives a sturdy tubing set that fits tightly and supports smooth exhaust flow for custom builds or swaps. It is clearly aimed at home fabricators and professionals who want a universal, slip-fit kit to build or repair exhaust systems.

Key Features

• 18-gauge piping walls: Provides a solid balance of strength and formability for welding and bending without excess weight.
• 2.5 in outlet size: The 2.5 in OD inlet and outlet is a common diameter that supports good exhaust flow and matches many mid-size systems.
• Slip fit joints: Slip fit connections make alignment and tack welding faster, simplifying fabrication for DIY installers.
• Mandrel bends: Computerized mandrel bends maintain a smooth internal radius to minimize turbulence and help maximize flow.
• Complete kit: Includes straight pipes and 45, 90 and 180 U-bends so users can route a full custom exhaust without buying additional sections.
• Mild steel construction: Allows easy welding with common methods and flux core, making it convenient for home shops.

Who It's For

This kit is best for DIY fabricators, small shop mechanics and enthusiasts building or repairing mid-size exhaust systems who need a ready set of mandrel-bent tubing in 2.5 in OD. It suits projects where weldability and a range of bend angles are important, such as swaps, muffler deletes, custom headers and exhaust routing for trucks and SUVs.

Those who should look elsewhere include builders who need stainless steel for long-term corrosion resistance or anyone requiring nonstandard diameters; this kit is mild steel and optimized for versatility and affordability rather than ultimate rust resistance.

Pros & Cons

Pros

• Good buildability thanks to 18-gauge walls and slip-fit joints that make welding straightforward.
• Includes a useful selection of bends and straights so many custom runs can be completed from one kit.
• Mandrel-bent sections preserve internal flow for improved exhaust performance.
• Customers report strong value for money and tight fit between pieces for easy assembly.

Cons

• Made of mild steel so long-term rust resistance varies by environment; some users report surface rust over time.
• Not a stainless option, so extra coating or wrapping may be needed for corrosive climates.

Specifications

Material	Mild steel
Wall thickness	18-gauge
Inlet / outlet size	2.5 in OD
Kit contents	2x 48 in straights, 2x 90 deg, 2x 45 deg, 2x 180 deg U-bends
Bend type	Computerized mandrel bends
Joint type	Slip fit

Our Verdict

The ZTL-25RAW-8P is a practical, cost-effective exhaust tubing kit for anyone building a custom 2.5 in system who values weldability and a complete range of bends. It offers good durability and flow-friendly mandrel bends at an attractive price, but builders in corrosive environments should plan protective coatings or choose stainless alternatives.

Frequently Asked Questions

Will these pieces weld well with flux core?
Yes, customers report the mild steel and 18-gauge walls weld easily with flux core and standard MIG processes.

Are the bends mandrel formed?
Yes, the kit uses computerized mandrel bends to maintain smooth internal radii and minimize flow restriction.

Is this kit rust resistant?
Not inherently; mild steel can surface rust over time, so painting or coating is recommended for long-term corrosion protection.