It seemed like a revolution in auto design when BASF and DuPont engineers developed in the 1980s a cost-effective way to replace cast metals with molded nylon for automotive intake manifolds. It was a dramatic move that substantially reduced automotive weight.
Newer iterations use less expensive resins. Engineers at another German company, Röchling Automotive, say they have developed improved intake manifolds made from polypropylene, which has a lower density than nylon (polyamide). And that means more weight reduction, lower costs and improved acoustics.
Röchling’s first intake manifold applications using polypropylene are a one-liter three-cylinder VW engine in Brazil and Europe and a 1.6 liter four-cylinder engine in China.
“The PP intake manifold is the first and only one of its kind in China and Brazil to date. It’s also the first three-cylinder application in Europe, and particularly demanding in terms of acoustics,” says Marco Barbolini, product manager for the air intake system at Röchling Automotive. “These are Röchling’s first intake manifold applications using polypropylene. To be able to substitute for polyamide, there were a number of challenges to overcome. But we were rewarded with improved acoustics.”
The 15% cost advantage over nylon is made possible by the need for fewer processing steps plus the lower melting temperature and density. Plus there are multiple suppliers of polypropylene material is readily available around the globe.
Röchling says itreaches almost the same continuous operating temperature as with nylon. However it does require special heat stabilization.