[jlaudio11]

Originally Posted by Osbornsm

Can someone explain this to me like i'm 5 ???

Piston rings are set from the factory with a specific gap in them based on their intended purpose. The stock Lt1 ring gap is relatively tight for a boosted application. That tight gap is good for the engine's overall efficiency and keeping combustion up above the piston and out the exhaust. When you introduce boost, those cylinder pressures go up and so does heat. With that heat the rings expand. With the small gap they can only expand so far before the tips touch and have nowhere to go. When this happens they fold up or down into the piston, thus breaking ringlands or the area the ring rides in. Generally boosted applications sacrifice some efficiency for safety under boost and have looser ring gaps.

[Osbornsm]

Originally Posted by jlaudio11

Piston rings are set from the factory with a specific gap in them based on their intended purpose. The stock Lt1 ring gap is relatively tight for a boosted application. That tight gap is good for the engine's overall efficiency and keeping combustion up above the piston and out the exhaust. When you introduce boost, those cylinder pressures go up and so does heat. With that heat the rings expand. With the small gap they can only expand so far before the tips touch and have nowhere to go. When this happens they fold up or down into the piston, thus breaking ringlands or the area the ring rides in. Generally boosted applications sacrifice some efficiency for safety under boost and have looser ring gaps.

Solid.


Thank you for learning me something today

[Wyzz Kydd]

Originally Posted by jlaudio11

Piston rings are set from the factory with a specific gap in them based on their intended purpose. The stock Lt1 ring gap is relatively tight for a boosted application. That tight gap is good for the engine's overall efficiency and keeping combustion up above the piston and out the exhaust. When you introduce boost, those cylinder pressures go up and so does heat. With that heat the rings expand. With the small gap they can only expand so far before the tips touch and have nowhere to go. When this happens they fold up or down into the piston, thus breaking ringlands or the area the ring rides in. Generally boosted applications sacrifice some efficiency for safety under boost and have looser ring gaps.

What about an older LT1 with more miles on it. Would the ring gap have opened up through use and thus be more suitable for boost?

[jlaudio11]

Originally Posted by Wyzz Kydd

What about an older LT1 with more miles on it. Would the ring gap have opened up through use and thus be more suitable for boost?

That was somewhat general consensus on ls truck engines but from memory those engines started life with more ring gap to begin with, like .016 compared to .006 on a gen v lt engine. I haven’t seen a high mileage gen v to really test that theory but I don’t see them opening that much too be very safe for boost.

[Kerry]

geez some old fables never die

[Kamero6]

Originally Posted by Wyzz Kydd

What about an older LT1 with more miles on it. Would the ring gap have opened up through use and thus be more suitable for boost?

Yea but at that point you have more wear and blow by. That isn't good to add 200-300 hp to the engine.
Blow by, if its considerable, will burn the oil coating in the cylinder walls and also heat up the oil in the oil pan.
Wear in cylinder walls isn't good for boost or high rpms. Rings floating is another bad thing that might happen.

A set of rings and gastkets is cheap compared to a new engine. The issue is to to all that work. Only worth it if you DIY.

[Kamero6]

About the topic, It can be totally safe if you build it taking in safety factors, with a serious tune, and not chasing the last HP possible on a cold day...

The devil is in the details.