Housing, Turbine, GTW3884R, T3 Undivided .63 A/R, w/ T31 4 bolt (aka 2.5 4B) exit

The Garrett GTW3884R T3 undivided .63 A/R turbine housing is engineered for builders who demand precise exhaust housing sizing without sacrificing compact packaging. Designed for GTW3884R-based turbocharger builds, this housing is the choice for enthusiasts who need a proven T31 exit configuration for reliable down-pipe integration. It’s built for serious performance applications where fitment accuracy and flow characteristics matter as much as raw output.

Specifications

• Turbine Housing Model: GTW3884R
• Turbine Entry Type: T3 Undivided
• A/R Ratio: .63
• Exit Flange Type: T31 4 Bolt (aka 2.5 4B)
• Also Known As: T31 4 Bolt exit referred to as 2.5 4B

Performance & Application

This turbine housing is matched to the GTW3884R platform, making it well suited for builds centered around that turbocharger. The T3 undivided entry design is intended for applications requiring straightforward, efficient exhaust gas delivery into the turbine wheel. The .63 A/R ratio configuration is optimized for compact turbo builds requiring efficient exhaust flow. Pairing this housing with the correct downstream components ensures direct bolt-on compatibility for down-pipe side connections.

What’s Included

• Flange, “T31″ Narrow 4 Bolt 2.5” (down-pipe side) — Product Code: ATP-FLS-084
• Gasket, “T31″ Narrow 4 Bolt 2.5” (down-pipe side) — Product Code: ATP-GSK-012

Frequently Asked Questions

What is the A/R ratio of this turbine housing?

This turbine housing is configured with a .63 A/R ratio.

What does “2.5 4B” refer to?

“2.5 4B” is an alternate name for the T31 narrow 4-bolt 2.5″ exit flange used on this housing.

What turbine entry configuration does this housing use?

This housing uses a T3 undivided turbine entry design.

Does this housing come with the flange and gasket needed for installation?

Yes, it includes a T31 narrow 4-bolt 2.5″ flange (down-pipe side) and matching gasket (down-pipe side).

For builders running the GTW3884R platform who need a precisely matched .63 A/R T3 undivided turbine housing with T31 4-bolt exit compatibility, this housing delivers exactly the fitment and flow characteristics the build demands.