Mandrel Bend Technical Data & Specifications
Precision-built bends for performance fabrication
At TrueMandrel, every bend is engineered for accuracy and repeatability. The information below helps builders, fabricators, and performance enthusiasts select the best material, bend radius, and diameter for their project.
📏 Material Availability
| Material Type | Available Sizes | Notes |
|---|---|---|
| Mild Steel | 1″ – 3″ | Standard, easy to weld, affordable. |
| 304 Stainless Steel | 1″ – 4″ | High corrosion resistance and strength. |
| Aluminized Steel | 2″ – 5″ | Affordable corrosion-resistant option. |
| 409 Stainless Steel | 2″, 2.5″, 3″ | OEM-grade stainless for production systems. |
📐 Bend Specifications
| Tubing OD | CLR (in) | Leg Lengths | Available Materials |
|---|---|---|---|
| 1″ | 3.0″ | Standard | Mild Steel, 304SS |
| 1-5/8″ | 3.0″ | 4″ | Mild Steel, 304SS |
| 1-3/4″ | 3.0″ | 4″ | Mild Steel, 304SS |
| 1-7/8″ | 3.0″ | 4″ | Mild Steel, 304SS |
| 2″ | 3.0″ | 4″ | Mild Steel, 304SS, Aluminized, 409 |
| 2-1/4″ | 4.0″ | 5″ | Mild Steel, 304SS, Aluminized |
| 2-1/2″ | 4.0″ | 5″ | Mild Steel, 304SS, Aluminized, 409 |
| 3″ | 4.5″ | 6″ | Mild Steel, 304SS, Aluminized, 409 |
| 3-1/2″ | 5.0″ | 11″ | 304SS, Aluminized |
| 4″ | 5.0″ | 7″ | Mild Steel, 304SS, Aluminized |
| 5″ | 6.0″ | 11″ or None | Mild Steel, 304SS, Aluminized |
⚙️ Recommended Exhaust Tube Size by Horsepower
| Engine HP | Suggested Tube Diameter (Single) | Suggested Tube Diameter (Dual) | Approx. Flow (CFM) |
|---|---|---|---|
| Up to 200 HP | 2.0″ – 2.25″ | 1.75″ | ≈ 440 |
| 200 – 300 HP | 2.25″ – 2.5″ | 2.0″ | ≈ 660 |
| 300 – 400 HP | 2.5″ – 3.0″ | 2.25″ | ≈ 880 |
| 400 – 600 HP | 3.0″ – 3.5″ | 2.5″ – 2.75″ | ≈ 1320 |
| 600 – 800 HP | 3.5″ – 4.0″ | 3.0″ | ≈ 1760 |
| 800+ HP | 4.0″ – 5.0″ | 3.5″ – 4.0″ | ≈ 2200+ |
Equation for reference: CFM = (Horsepower × 2.2)
Diameter Estimate: √(CFM ÷ 115)
💡 Fabrication Tips
- Mock up and tack weld before final welding to maintain alignment.
- Back-purge stainless tubing for clean, strong welds.
- Remove aluminized coating at weld joints before welding.
- Measure CLR from the tube centerline for accuracy.
🔍 Material Comparison
| Factor | Mild Steel | Aluminized | 304SS | 409SS |
|---|---|---|---|---|
| Corrosion Resistance | ★★☆☆☆ | ★★★☆☆ | ★★★★★ | ★★★★☆ |
| Weldability | ★★★★★ | ★★★★☆ | ★★★★☆ | ★★★★☆ |
| Cost | $ | $$ | $$$$ | $$$ |
| Aesthetic Finish | ★★☆☆☆ | ★★★☆☆ | ★★★★★ | ★★★★☆ |
| Durability | ★★★☆☆ | ★★★★☆ | ★★★★★ | ★★★★☆ |
