The CSF Manifold is made from Billet Aluminum and 100% TIG Welded for strength, which allows it to be able to withstand higher boost pressures compared to the OEM plastic manifold. Aluminum has higher thermal conductivity than plastic resulting in a higher rate of heat transfer between the cylinder head and manifold. Adding the Thermal Rejection Spacer reduces heat transfer between the two metal components (cylinder head & manifold). The spacer absorbs the heat from the cylinder head and dissipates it rather than transferring it to the manifold. The CSF Thermal Rejection Competition Spacer was designed for vehicles competing in motorsports who demand the absolute best cooling in order to gain a competitive edge. However, including this spacer offers significant advantages to any vehicle.

This Part Fits:

Year	Make	Model	Submodel
2016-2018	BMW	340i	Base
2017-2019	BMW	340i GT xDrive	Base
2016-2018	BMW	340i xDrive	Base
2017-2020	BMW	440i	Base
2017-2020	BMW	440i Gran Coupe	Base
2017-2020	BMW	440i xDrive	Base
2017-2020	BMW	440i xDrive Gran Coupe	Base
2017-2019	BMW	540i	Base
2017-2019	BMW	540i xDrive	Base
2018-2019	BMW	640i xDrive Gran Turismo	Base
2017-2019	BMW	740i	Base
2017-2019	BMW	740i xDrive	Base
2018-2021	BMW	M240i	Base
2017-2021	BMW	M240i xDrive	Base
2018-2019	BMW	X3	M40i
2019	BMW	X4	M40i