Junker wants to design and make engines.
Last week, it even changed the name of Cosworth - famed in racing circles - to Mahle Powertrain.
"Cosworth was linked to Ford racing and Audi, and this made it difficult for us to establish relations with other companies," Mahle Chairman Heinz Junker said at a press briefing here.
The British unit gives Mahle a sixth area of business: engineering services and hardware/software development.
Mahle Powertrain can manufacture engines in low to medium volume and produce cylinder heads and other major components. It currently makes many of Audi's five-valve cylinder heads and machines heads for the Lamborghini Gallardo.
Mahle's five other product areas are piston systems, where it is world leader; cylinder components; valve train; and air and liquid management systems.
Adding Cosworth's manufacturing and engineering helped Mahle win new development work for existing customers and lets it do in-house research, Junker said.
He expects automakers to outsource more engineering work and he thinks Mahle's manufacturing capability could give it an edge over rivals AVL of Austria, FEV in Germany, and UK-based Ricardo.
"This is definitely a useful synergy," said analyst Antonio Ferreira of CSM Worldwide. "What Mahle does requires a lot of partnership with engine manufacturers."