Nerd’s Eye View: LA Auto Show Part I – The Engines
Khiem Dinh is an engineer for Honeywell Turbo Technologies at the time of this writing. All statements and opinions expressed by Khiem Dinh are solely those of Khiem Dinh and not reflective of Honeywell Turbo Technologies.
Times are a changin’ and they be changin’ quick. Fuel economy is the name of the game and the OEMs are releasing new powertrain configurations as quickly as they can release new vehicles. Part of that equation involves turbos which should make every gearhead happy. The other part of the equation is electrification. The fastest road course race cars on Earth are hybrids, so electrification should be embraced. Enough rambling, on with the engine show!
Why turbos? Go back and read my article on engine downsizing. Back in the day, BMW and Honda were decidedly against turbochargers as they weren’t ‘pure’. I think they viewed turbos as cheating when it came to making power. Well, times have changed and the only way to make big power while having respectable fuel economy is to go turbo. I’m pretty sure EVERY BMW is now turbocharged and Honda is releasing a turbocharged 2.0L Civic soon. Ford and GM are putting turbo engines in nearly every car. VW/Audi has of course been fans of putting turbos in across their product line and everyone else is now playing catchup.
Fifteen years ago, if you had said that Porsche’s premiere showcased vehicle would be an SUV with a twin-turbo V6, you probably would have been lashed a thousand times with bratwurst and thrown out of the bier garden. Yet, here is the 3.6L, 400hp, twin-turbo V6 available in the Macan. It’ll do 0-60 in 4.6 seconds, so you better have some power under your hood if you decide to take on that rich soccer mom in the next lane.
The dual overhead cams act directly on the buckets to actuate the valves. This is one spot DLC coating is commonly used to reduce friction though I don’t know if Porsche used it specifically on this engine. I wouldn’t bet against it though. The timing chain looks to be quite beefy; I know the 4b11 engine in the Evo X has issues with chain stretch so hopefully the chain on this Porsche engine should not have the same issue. A common trend nowadays as it relates to turbos is to have the exhaust manifold and turbine housing of the turbo cast as one piece as seen here.
The other common trend is to have a plastic intake manifold. Porsche uses what it calls a ‘dual flow intake’ which just looks like a separate plenum for each bank of cylinders. By keeping the banks separated, it is said to improve resonance tuning to improve scavenging. One thing I find interesting is the manifold basically has a long runner before dumping into the plenum to feed each bank of three cylinders. Your typical Japanese four cylinder engine (old school at least) just has the throttle body attached to the end of the plenum. I imagine the extra length in the Porsche manifold is for resonance tuning to beef up the bottom-end torque. The exterior of the manifolds are ribbed to add strength.
The oil system on this engine is meant for serious business. It uses a dry-sump system along with a baffle (which I believe is the black vertical thing in the middle of the pan). Oh yeah, that’s an oil cooler too. Should the soccer mom (I guess that would be football mom in Europe) decide to attack the Nurburgring, the Macan seems capable.