
Replacing the exhaust manifolds (swapping the standard cast iron ones for stainless steel parts) means that, with similar flow cross-sections, exhaust gases can escape more easily due to reduced friction within the exhaust system. This allows for better exhaust gas clearance and, consequently, better cylinder filling, enabling high revs with hardly any loss of performance.
As engines become more efficient from the factory, losses in the exhaust systems become more noticeable. A properly designed exhaust manifold is essential when upgrading an engine. Any factor that reduces power or makes combustion less efficient causes the engine to burn more fuel for the same power output. In a car, it is common to see a reduction of more than 15% in horsepower and a 10% drop in fuel economy due to the restriction of the original exhaust system. The first step in upgrading an engine is to replace the original manifold with one featuring separate outlets.
Exhaust manifolds are particularly suitable for boosting mid- and high-range performance in modern cars, which typically run above 5,000 rpm and rarely operate below 3,000 rpm. This results in power increases of between 4 and 8 DIN hp, without affecting fuel consumption.
All our manifold fitting kits come with the necessary accessories for installation. From the cylinder head gasket to most of the bolts for the mounts, with the exception of those for the engine cylinder head.