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Frequently asked questions about cars and motorcycles

Carburetor and Intake Manifold Polishing

Model: BMW Serie 5 E39 - Years 1995-2003
Part: Carburetor

A perfect polish of the internal body of the carburetor and the corresponding intake manifold will make the surface so smooth that it minimizes friction and turbulence in the mixture flow, thus improving power delivery. This is a procedure that tuners always perform on the intake ports of the cylinders to enhance airflow. Start by removing the throttle plates and extracting the associated control rods to free the internal body of the carburetor. At this point, begin wet sanding using fine-grit sandpaper (2000), then proceed to polish with special abrasive rubber tips, lubricating them with penetrating oil. Finally, perform the actual polishing with a dedicated paste. Repeat the same steps on the manifold.

Updated on 18 February 2026 by ScegliAuto

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