Turbo Accessories
V-BAND 3.5″ CARBON STEEL A36 TURBO INLET FLANGE 1/2″ HEAVY DUTY
KEY FACT
The V-Band 3.5″ Turbo Inlet Flange is a 1/2″ (12.7 mm) Carbon Steel A36 precision-machined component designed for any turbocharger with a 3.5-inch V-Band inlet housing. CNC laser-cut to ±0.003-inch flatness, ASTM A36 certified, and priced at $29.28 — in stock with same-day dispatch.
SKU: TIFVBANDCARBONSTEELHEAVYDUTY
It suits any turbocharger with a 3.5-inch V-Band inlet housing, providing a clamp-based seal (V-Band clamp) with 360-degree rotation for tight manifold routing. Manufactured from ASTM A36 carbon steel and zinc-phosphate primed, it is the most cost-effective and weldable option — suited to builds that will be ceramic-coated after fabrication. The 1/2-inch heavy-duty thickness is recommended for diesel engines, large-displacement builds, and any setup with a rigid unsupported downpipe. Every flange is CNC laser-cut and surface-ground to ±0.003-inch flatness with bolt holes reamed to H7 tolerance, providing a gas-tight metal-to-metal seal without a gasket on properly prepared turbos.
✓ Free shipping on orders over $150
✓ Same-day dispatch on orders before 2 PM EST
✓ 30-day returns for unused items
✓ Pickup available in Miami, FL 33172 — by appointment
Technical Specifications
| Inlet Port Size | 3.50 in bore |
|---|---|
| Flange O.D. | 4.25 in OD |
| Bolt Pattern | V-Band clamp |
| Thickness | 1/2″ (12.7 mm) |
| Max Temperature | 982°C / 1800°F |
| Material | Carbon Steel A36 |
| Standard | ASTM A36 |
| Surface Finish | Zinc-phosphate primed |
| Flatness | ±0.003 in |
| Bore Tolerance | H7 reamed |
Material Comparison Guide
304 Stainless vs 316 Stainless vs Carbon Steel vs Inconel 625 — your selection is highlighted
| Specification | 304 Stainless | 316 Stainless | Carbon Steel YOUR SELECTION | Inconel 625 |
|---|---|---|---|---|
| Max Continuous Temp | 871°C (1600°F) | 925°C (1700°F) | 425°C (800°F) | 1093°C (2000°F) |
| Corrosion Resistance | Good | Excellent | Poor (needs coating) | Excellent |
| Weldability | Excellent | Excellent | Excellent | Good |
| Cost (relative) | $$ | $$$ | $ | $$$$ |
| Best For | Street / track | Marine / E85 / diesel | Budget builds / coated manifolds | Extreme boost / compound turbos |
| Standard | ASTM A240 304 | ASTM A240 316 | ASTM A36 | AMS 5666 |
| Recommended Gasket | Optional | Optional | Recommended | Optional |
Frequently Asked Questions
About the V-Band 3.5″ Carbon Steel A36 Turbo Inlet Flange 1/2″ Heavy Duty
Does this flange fit my turbo?
Yes — this V-Band flange fits any turbocharger with a 3.5-inch V-Band inlet housing, including many Garrett GTX, BorgWarner EFR, and Turbonetics units with V-Band inlet configurations.
Why should I choose Carbon Steel A36 for a turbo inlet flange?
Carbon steel A36 is the most weldable material and the lowest-cost option. It is the correct choice when the flange will be welded into a custom manifold that will then be ceramic-coated or powder-coated. It is not recommended for exposed installations.
Should I choose the 3/8-inch or 1/2-inch thickness?
The 1/2-inch (12.7 mm) heavy-duty thickness is correct for diesel engines, large-displacement V8 builds, and any application where the downpipe is rigid and places bending stress on the flange. For lighter gasoline builds, the standard 3/8-inch option saves weight and cost.
How do I install the V-Band 3.5″ turbo inlet flange?
Clean the turbo inlet face and remove all old gasket material. Align the flange with the N/A bolt holes and thread the V-Band bolts in finger-tight. Torque in a cross pattern to spec (M8: 18–25 Nm · M10: 30–40 Nm · M12: 50–65 Nm). A 1/16-inch Cometic MLS gasket is recommended on builds over 25 PSI.
Does this flange need a gasket?
A gasket is not strictly required — the face is ground to Ra 1.6 μm, which creates a metal-to-metal seal on most turbos. However, a 1/16-inch multi-layer steel (MLS) gasket is recommended for builds over 25 PSI boost or on turbos with minor surface irregularities.
What is the price of the V-Band 3.5″ Carbon Steel A36 Turbo Inlet Flange 1/2″ Heavy Duty?
The V-Band 3.5″ Carbon Steel A36 Turbo Inlet Flange 1/2″ Heavy Duty is $29.28 per piece with free shipping on orders over $150. It is in stock and ships same day when ordered before 2 PM EST.