BMW E21/E30 4-2-1 exhaust manifold (1,8/2,0 4-cyl)

For the M10-type engine (chain-driven camshafts). Pipe diameters (mm) 44.5-> 44.5-> 50.8. Mild steel with thermal isolating TechLine BlackSatin ceramic coating. Designed for max. 170hp. Provides very wide power range.

Collector part is fitted with springs. That eliminates the risk of primary pipe cracking due to engine movement. Also that makes it possible to tune power range. Shortening of seconary pipes will move power range to higher revs.

Lamda sond boss at outlet pipe.

Recommended exhaust system size 2" (up to 150 hp) or bigger.   

E21: Weld-together exhaust system kits available. 

E30: Choose universal pipes, curves and silencers to build the exhaust system. https://martelius.com/en/universal-parts