Turbo Accessories
T4 304 STAINLESS STEEL TURBO INLET FLANGE 1/2″ HEAVY DUTY
KEY FACT
The T4 Turbo Inlet Flange is a 1/2″ (12.7 mm) 304 Stainless Steel 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 A240 304 certified, and priced at $39.04 — in stock with same-day dispatch.
SKU: TIFT4STAINLESSHEAVYDUTY
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 A240 304 stainless steel, it resists oxidation to 871°C (1600°F) — the industry-standard specification for street and track turbo builds. 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 | 3.32 × 2.63 in |
|---|---|
| Flange O.D. | 4.65 × 3.65 in |
| Bolt Pattern | 4 × M10 |
| Thickness | 1/2″ (12.7 mm) |
| Max Temperature | 982°C / 1800°F |
| Material | 304 Stainless Steel |
| Standard | ASTM A240 304 |
| Surface Finish | Ra 1.6 μm mill finish |
| 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 YOUR SELECTION | 316 Stainless | Carbon Steel | 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 304 Stainless Steel Turbo Inlet Flange 1/2″ Heavy Duty
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 304 Stainless Steel for a turbo inlet flange?
304 stainless is the best all-round choice for most turbo builds. It resists heat to 871°C, welds easily, and costs significantly less than 316 or Inconel. It is ideal for gasoline engines running standard pump fuel or E30 and below.
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 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 304 Stainless Steel Turbo Inlet Flange 1/2″ Heavy Duty?
The T4 304 Stainless Steel Turbo Inlet Flange 1/2″ Heavy Duty is $39.04 per piece with free shipping on orders over $150. It is in stock and ships same day when ordered before 2 PM EST.