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

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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.]
I’m probably wrong but my interpretation of the original post was there were issues not only with rings but “loose” pistons. If there are issues with too much piston to cylinder wall clearance the pistons will rock.
 
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I’m probably wrong but my interpretation of the original post was there were issues not only with rings but “loose” pistons. If there are issues with too much piston to cylinder wall clearance the pistons will rock.
Ah, that’d be something different. and not very good.
 
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People want big screen displays, buttons and power everything that needs space and adds weight.
It’s not that hard to add CarPlay or Android Auto to an older car but it gets expensive quick.
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.
I know someone with a early 80s F-250. 460 carbed V8, single cab, 8’ bed. It’s the same size as a Tundra Crew Cab or a new F-150 SCrew with the 5’ bed. My Prius gets similar MPG as a Geo Metro, but you know what car I’d rather be in during a crash.
 
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When Hyundai engines go to an early grave, it's usually due to the owner's neglect.
The earlier Hyundai efforts weren’t great, they were Korean-built Mitsubishi engines with the same things that plagued 1980s-2000s Mitsu(and Mopar as well since the 2.4L 4G63/64 and 3.0L V6 were used in many K-Cars, minivans, Sebrings and the DSM lineup). The new in-house engines aren’t bad.
 

ChrisD46

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I’m probably wrong but my interpretation of the original post was there were issues not only with rings but “loose” pistons. If there are issues with too much piston to cylinder wall clearance the pistons will rock.
*Yes , the South Korean YouTube video states this .
 
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This has been the case with several different brands for the past few years. It's basically a race to accomplish the impossible for manufacturers. Vehicles that are increasing in weight due to safety standards also must increase in efficiency, without dramatically increasing cost. While the engines get better mpg, one could argue the increased oil consumption offsets any benefit to the environment.

Probably one of the main reasons many manufacturers are trying hard to go all EV, much easier to manufacture and the emissions issue gets passed on to someone else.
 
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*Good to hear ! ... ** I reference the South Korean YouTube video on the Smart Stream 2.5L engine pistons / rings .
And we have 2020, not 2021. They upgraded the oil pan and dipstick for 2021 to accommodate another half-quart of oil.

The real issues with this engine were software-related, and I had all the updates done. Hyundai, by rushing the engine out the door, fudged the programming.

It's an MPI/GDI engine, and they didn't get the air/fuel mixture right along with when to switch between GDI and MPI. I knew about the issues (and assumed problems with a new design), so I kept the OCIs very short (3K miles) and ran 5W-30 instead of 0W-20. I did that until I got the ECM updates for the mentioned problems. Now it's running M1 EP 0W-20, and the MPG is impressive.

If you have one of these or planning to get one, I wouldn't worry about it. Don't run the cheapest 0W-20 you can find in it (as in SuperTech, Castrol GTX, etc.), and you'll be fine.
 
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It's not because of CAFE. It's because of Hyundai :sneaky:
I beg to differ. BMW fitted low tension oil control rings in the 3 liter (and only the 3 l) version of the M54 engine. Why? To squeeze 0.04mpg out of the engine. After about 50k miles these engines started to burn oil. My old 2001 330Ci burned a quart of M1 0W40 every 500 miles or so. There are numerous things that can be done to the engine to reduce oil burning. I installed an oil catch can. It reduced oil burning some. The best "solution" is to use DMSO in the oil and dissolve the burned oil in the rings and the grooves.

Part 1: https://www.e46fanatics.com/threads/ultimate-engine-flush-process-part-1.1285390/
Part 2: https://www.e46fanatics.com/threads...the-engine-part-2-combustion-chamber.1285432/
 
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KISS keep it simple stupid!! anything that manufactures TRY makes us a beta tester!! ditto on the oversized over optioned tanks these days, BUT you bought it so its YOUR problem!!!
 
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KISS keep it simple stupid!! anything that manufactures TRY makes us a beta tester!! ditto on the oversized over optioned tanks these days, BUT you bought it so its YOUR problem!!!
Buying the bottom trim line is perhaps making the best of a lousy situation (by way of added vehicle complexity).
 
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A few years ago when gas was cheap,manufacturers made a lot of money as the consumer started chasing large SUV's and large PU trucks.Now gas is back up.The rings,piston dimension fit and thin oil to meet the CAFE rules ,makes you wish for some of the old vehicle sizes
 
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The B210 was quite the style disaster, notwithstanding it's fuel economy... 🙁
I got mixed-up... '74-'78 was one style; '79 up, another style... The latter, maybe not better, but perhaps fewer Japanese "style" embelishments (typical in the era).

Having said that, here are nifty Miniliites and a cool air dam (cool to my eye).
 

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I got mixed-up... '74-'78 was one style; '79 up, another style... The latter, maybe not better, but perhaps fewer Japanese "style" embelishments (typical in the era).

Having said that, here are nifty Miniliites and a cool air dam (cool to my eye).


I knew someone that owned a early B210. Great fuel economy but the interior was a lot of plastic and cheaply built. He had electrical problems as well as that was typical for those early Datsuns.

I remember everyone laughing at the Datsun pickups too. Toy trucks they were called. But they ran and ran and did whatever was asked of them.
 
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