2016 Chevy Cruze: lower weight, better engine!

[Vman455]

Originally Posted by Daox

You can already get the Cruze with a 1.4L turbo.

Different 1.4L turbo--the old one is a cast-iron block, new one is aluminum and 44 lbs lighter.

[jcp123]

But the turbo bearings are still oiled, no? That's where the oil-cooking happens.

[Daox]

Correct. The oil used to do the job of cooling and lubricating. Now, it mainly just does the lubrication part.

[2009Toyotoad]

Chevy has not a particularly stellar track record when it come to all aluminum engines. I refer to the 1975-76 Chevy Vega as an example. The Vega saga was part technology and part poor communications and documentation by GM in general over the entire process. As the Vega Saga is 40 years into past history lets hope those hard learned lessons were not forgotten.

[cRiPpLe_rOoStEr]

Originally Posted by jcp123

But the turbo bearings are still oiled, no? That's where the oil-cooking happens.

Sure. But nowadays some design improvements can be applied to newer turbochargers and its bearings in order to minimize the occurrence of oil coking, and also the specifications of lube oils have changed a lot. I have already seen many older vehicles retrofitted with a turbo and no supplementary oil pumps without any sign of oil coking into the turbo bearings.

[Vman455]

More information and pictures here.



GM claims Cd .29, and stop-start is standard.

[jcp123]

Originally Posted by cRiPpLe_rOoStEr

Sure. But nowadays some design improvements can be applied to newer turbochargers and its bearings in order to minimize the occurrence of oil coking, and also the specifications of lube oils have changed a lot. I have already seen many older vehicles retrofitted with a turbo and no supplementary oil pumps without any sign of oil coking into the turbo bearings.

Neat. Thanks! I always figured EOC would just fry a turbo, now I am starting to see why that's not necessarily so.

[cRiPpLe_rOoStEr]

Originally Posted by jcp123

I always figured EOC would just fry a turbo, now I am starting to see why that's not necessarily so.

Now that start-stop is so widespread in Euro cars, they couldn't take this risk. I have already observed it in a Mercedes-Benz A-Class and an Audi A3, both turbocharged and fitted with start-stop.

[kafer65]

I don't think you'd have a problem with excessive heat soaking into the bearing area in start/stop situations with well designed water cooled turbos. Hard load pulls of longer duration followed by shutdown might be of concern if you didn't have water there in a 1600-1800F environment. Even 10 seconds of idle circulation would mitigate that a bunch. I wonder if they have previsions to continue to circulate water and/or oil after shutoff since the trend is to move the accessories off of the engine and using ECU controlled electric motors.

[Smurf]

The new Cruze looks a lot better than the current generation. The headlight has a Colorado-esque appearance to it. The bottom grill is a little Ford looking, and the ridge behind the front wheel screams Mazda from the side... but definitely an improvement.