BMW E39 525D, 530D Downpipe

63mm Downpipe without catalyst or particulate filter for the following models:

• BMW E39 525D
• BMW E39 530D

Replaces OEM nr:

• 18100418187
• 18317785557
• 18317785911

By installing a larger bore downpipe backpressure in the exhaust drops which makes the turbo rev easier which means the turbo starts building pressure at lower RPM's. If during shifting the pressure drops it also builds back pressure faster. 

By only installing a larger diameter downpipe the horsepower rises between 15 and 20hp and torque also goes up by 25 to 30Nm. Combining a downpipe with chiptuning brings even more extra power.

A software update (chiptuning) would be advised.

This product is not intended for use on the open road.