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Message: <blockquote data-quote="stutaeng" data-source="post: 25839" data-attributes="member: 6175">I understand what you are saying. Yes, but that's too general of statement.I think the general idea is: for 2 engines to be making the same amount of work, the smaller one if working harder (and wearing faster), right?That's complicated because even if both engines are in the same family, they are not identical. In the 4.8 and the 5.3 case, the block is the same, so that doesn't matter. The rotating assemblies are what's different, with the 4.8 having a shorter stroke and different piston (but same bore). So the 4.8 will be obviously smaller, so it will be spinning at a higher RPM to make the same power. However, that doesn't necessarily mean it's going to be wearing faster. Piston design is pretty complicated, and you can actually design a piston with the same, or even less stresses than another piston for the same forces. This article discusses piston design in general terms: <a href="https://www.jepistons.com/je-auto-blog/how-fea-helps-simulate-engine-stress-on-a-computer/?srsltid=AfmBOopWM056jJJOCEQsyMOfmF4XmhFi6I4V-yuned6n7zPu447ERZwE" target="_blank">https://www.jepistons.com/je-auto-blog/how-fea-helps-simulate-engine-stress-on-a-computer/?srsltid=AfmBOopWM056jJJOCEQsyMOfmF4XmhFi6I4V-yuned6n7zPu447ERZwE</a>On the contrary, I speculate that a higher spinning (within a margin, of course) gas engine may actually live longer because it will have more lubrication and better materials on the newer engines vs the old engines. This isn't discussed much, but the other end of the spectrum is "lugging" a gas engine and the damage that causes to main/rod bearings because the low RPM (for the higher load):[ATTACH=full]4359[/ATTACH]Interesting fact: GM used Finite Element Analysis (FEA) on the LS engine design, back in the early 90s according Will Handzel on his book called "How to Build High-Performance LS1/LS6 V-8s". That was the early use of FEA on computers as far as I know.</blockquote>