New GDI Engines with Loose Fitting Rings / Pistons (Meeting CAFE = Oil Consumption & More Wear) ?

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The new Hyundai / Kia Smart Stream 2.5L GDI engine has been singled out as having loose fitting rings / piston (among other things) in an effort to squeeze out more miles per gallon of gas . This is resulting in oil consumption as oil is getting past the rings and burning off along with scuffed cylinder walls . I believe Hyundai / Kia is not the only 2021 or newer GDI engine to have this concern in an attempt to increase gas milage . Is there another way to meet CAFE's newer standards without resorting to loose fitting rings / piston in newer GDI engines which results in more oil consumption and cylinder wall wear ?
 
I'm a little confused. How would loose rings cause cylinder wall wear? The piston would rock regardless; most of the piston surface is below the rings, and would have a cushion of oil, regardless of what the rings are doing.

With PFI I'd think oil in the cylinder would cause problems, oil tends to effectively lower octane, right? but I'm not sure what happens with DI. I'm guessing very similar thing, which with higher cylinder pressures would seemingly cause problems quicker. Just a swag though.

Nothing new with low tension rings though, been around for a while. And last I knew, back when we had non-low tension rings is when we had cylinder wall wear issues. ;) [Apples and oranges I know, oil 20-30 years ago simply did not compare with what we now have.]
 
We have one of those 2.5L engines in our 2020 Sonata. It's running Mobil 1 EP 0W-20. No oil consumption issues here. The vehicle gets 44 highway MPH, 28 city.
 
Seems like they'll do anything to save a millionth of a billionth of a tiny non-existent fume before it poofs away! CAFE needs to come check out all the gas pumps and see how they drip drip drip on the ground when you remove the nozzle from filling up your car.
Yep, the car might drive another foot on a tankful of gas. But hey with $5/gallon gas those feet add up, 5280 of them will get you a mile. ;)
 
The new Hyundai / Kia Smart Stream 2.5L GDI engine has been singled out as having loose fitting rings / piston (among other things) in an effort to squeeze out more miles per gallon of gas . This is resulting in oil consumption as oil is getting past the rings and burning off along with scuffed cylinder walls . I believe Hyundai / Kia is not the only 2021 or newer GDI engine to have this concern in an attempt to increase gas milage . Is there another way to meet CAFE's newer standards without resorting to loose fitting rings / piston in newer GDI engines which results in more oil consumption and cylinder wall wear ?
Vehicles could go back to being smaller again instead of the land barges we’re accustomed to today…

I saw an 80’s vintage Camry the other day and it was smaller than the new Corolla. My ‘94 Civic w/1.5 NA got better MPG than behemoth Civic w/1.5T of today. And my neighbors early 90’s F250 w/7.3 is smaller than the new F150’s.
 
Vehicles could go back to being smaller again instead of the land barges we’re accustomed to today…


I think it’s a regional observation. Where I am the larger vehicles are the minority. Tons of compact crossovers and smaller vehicles. Pickups are the one exception and that may change once reality sets in for owners filling up their Ford F950 😁
 
Vehicles could go back to being smaller again instead of the land barges we’re accustomed to today…

I saw an 80’s vintage Camry the other day and it was smaller than the new Corolla. My ‘94 Civic w/1.5 NA got better MPG than behemoth Civic w/1.5T of today. And my neighbors early 90’s F250 w/7.3 is smaller than the new F150’s.
Right?

Going OT I know, but my cheap little bare bones 2015 Nissan versa sedan with a 1.6L multi-port injected engine and conventional 4spd automatic averages 36mpg tank to tank without even trying. It is like going back to 1992 when you're in it.. That's the problem. People want big screen displays, buttons and power everything that needs space and adds weight.
 
I think it’s a regional observation. Where I am the larger vehicles are the minority. Tons of compact crossovers and smaller vehicles. Pickups are the one exception and that may change once reality sets in for owners filling up their Ford F950 😁
Ha! Yeah, I’m in Texas…. If you ain’t got a big truck or Tahoe you ain’t country ‘nough.
 
Right?

Going OT I know, but my cheap little bare bones 2015 Nissan versa sedan with a 1.6L multi-port injected engine and conventional 4spd automatic averages 36mpg tank to tank without even trying. It is like going back to 1992 when you're in it.. That's the problem. People want big screen displays, buttons and power everything that needs space and adds weight.
I kinda like my 90’s Camry. It looks smaller than my newer ones but feels right sized. Low belt line, small pillars, simple design.

Only problem is, its a 90’s car… in the rustbelt… :( its fate is sealed.
 
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