Simons 4 branch manifold

Exhaust manifold 4-1

Model: Amazon, 140
Engine: B18-B20

Inner diameter of primary tubes: 34.5mm
The primary tubes join together to form a 3" collector
Length of primary tube: about 68cm
The manifold tapers down to 55mm (internally) 
Thickness of the flange: 10mm

Use the adaptor pipe that comes with cones down to 2 "to fit the Simons 2" exhaust systems
037-E