Tomei Expreme Twin Scroll Exhaust Manifold/Headers

Note: This is NOT suitable for Liberty GT EJ20 models with VF38/VF44/VF45 twin-scroll turbo. This is only suitable for JDM STI EJ20 models

With many exhaust manifolds released so far, we've always designed our headers with Performance, Reliability and quality aspects in mind. Now we have a new model that is compatible with GDB, GRB and GVB. Introducing the highly acclaimed EJ twin scroll EXPREME header. With the very best of the TOMEI exhaust technology, this new design will deliver balanced optimised performance for power, torque and feeling.

PIPE DIAMETER & BEND ANGLES

(a) MAIN PIPE ：Φ42.7

• The 42.7mm pipe diameter was chosen from the exhaust port to the collector to retain the stock like response.

(b) COLLECTOR ： Φ45.0

• A thicker than normal pipe was chosen to increase durability to handle high horsepower & high boost applications.

(c) TURBO SUPPORT PIPE ： Φ45.0

• Guides the exhaust gases more efficiently to maximize the Turbos performance potential.　

(d) LEFT BANK

• Top priority was given to this section, to be as close to straight as possible.

(e) RIGHT BANK

• A larger radial bend to the merging section was decided to minimize heat saturation to the oil sump.

(f) MERGE SECTION

• The acute angles allows a smooth extraction of gas flow from each bank. 

NON-STEPPED PORT DESIGN

REINFORCED FLANGE & LOST WAX COLLECTOR

• Exhaust Manifold
• Support Pipe
• E/G – Exh – Support pipe Gasket
• Turbin – Front Pipe Gasket
• Support Pipe – Turbine Gasket
• Cap Bolt
• Flat Washer
• Flange Nut
• Sutud Bolt
• Bandage
• Bandage Band
• Bolt Smooth Paste

This is NOT suitable for Liberty GT EJ20 models with VF38/VF44/VF45 twin-scroll turbo. This is only suitable for JDM STI EJ20 models.