Turbo Accessories
T4 CARBON STEEL A36 TURBO INLET FLANGE 3/8″ STANDARD
KEY FACT
The T4 Turbo Inlet Flange is a 3/8″ (9.5 mm) Carbon Steel A36 precision-machined component designed for Garrett T04E, Garrett T4, Precision 6262, and equivalent T4-footprint turbos. CNC laser-cut to ±0.003-inch flatness, ASTM A36 certified, and priced at $22.00 — in stock with same-day dispatch.
SKU: TIFT4CARBONSTEELSTANDARD
It is compatible with all T4-footprint turbos — Garrett T04E, Garrett T4, Precision 6262, and equivalent units — via the standard T4 4-bolt pattern (4 × M10). 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 3/8-inch standard thickness suits the vast majority of passenger car and light truck builds. 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 | 3.32 × 2.63 in |
|---|---|
| Flange O.D. | 4.65 × 3.65 in |
| Bolt Pattern | 4 × M10 |
| Thickness | 3/8″ (9.5 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 T4 Carbon Steel A36 Turbo Inlet Flange 3/8″ Standard
Does this flange fit my turbo?
Yes — the T4 inlet flange fits all T4-footprint turbos, including the Garrett T04E, Garrett T4, Precision 6262, and similar. It is not compatible with T3 or T6 footprint turbos without an adapter.
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?
For most builds, the 3/8-inch (9.5 mm) standard thickness is sufficient. Choose the 1/2-inch heavy-duty option only if you have a diesel engine, a large-displacement V8 with a rigid downpipe, or a setup that places significant cantilever stress on the flange joint.
How do I install the T4 turbo inlet flange?
Clean the turbo inlet face and remove all old gasket material. Align the flange with the 4 bolt holes and thread the M10 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 T4 Carbon Steel A36 Turbo Inlet Flange 3/8″ Standard?
The T4 Carbon Steel A36 Turbo Inlet Flange 3/8″ Standard is $22.00 per piece with free shipping on orders over $150. It is in stock and ships same day when ordered before 2 PM EST.