The factory downpipe on the BMW F30 328i N20 includes a restrictive catalytic converter that creates unnecessary back pressure. While this helps meet emissions requirements, it also limits the turbocharger's efficiency and reduces the engine's performance potential.
The factory downpipe connects the turbocharger to the rest of the exhaust system. While the OEM component is designed to meet strict emissions and noise regulations, it also creates significant exhaust restriction.
A catless performance downpipe removes the restrictive catalytic converter, allowing exhaust gases to exit the turbocharger far more efficiently. The result is:
Before selecting components, it is important to determine the goal of the vehicle build. Every exhaust system is designed around the vehicle’s intended use, power level, and available space.
Common applications include:
As soon as you push your engine beyond factory limits, the stock valve springs become a weak point.
At higher revs, factory springs cannot close the valves fast enough. This leads to valve float, where the valve no longer follows the camshaft profile correctly.
The TrackAttack Pro was developed using Hoosier’s proprietary H-DNA technology, incorporating over 65 years of racing experience into a tire designed for both street and track use. Unlike traditional street tires that prioritize comfort above all else, the TrackAttack Pro was engineered for drivers who want motorsport-level performance every time they get behind the wheel.
The Hoosier R7 was developed for dedicated racing applications where ultimate performance is the priority. Unlike traditional high-performance street tires, the R7 is engineered specifically for racetrack use, delivering significantly higher levels of grip, responsiveness, and cornering capability. The tire is commonly used in:
A badly built exhaust system rarely fails immediately. Problems usually appear over time through:
The camshaft controls:
These factors directly affect:
The story began when John Botha was gifted an original spare GT40 body that belonged to a GT40 campaigned and raced in South Africa. Having spent several years working extensively on GT40 chassis P/1024, Botha possessed an intimate understanding of the car's engineering and construction.
Fatigue fracture is the most common valve spring failure mode. A spring cycling at 7,000 RPM opens and closes each valve 3,500 times per minute — that is 210,000 stress cycles per hour. Over time, micro-cracks initiate and propagate until the wire breaks.
RestoMod promotes the South African aftermarket industry by keeping everyone updated on its latest happenings.
Stay informed on our latest news!
