What causes engine wear is unburned fuel after the power stroke, that creates carbon deposits which rob the spark needed for the next power stroke and contaminate the oil and cylinder walls with abrasive deposits that kill the rings.
Old engines had a fraction of the spark that modern coil packs provide, older engines had fuel delivery systems that could not adjust on the fly (carburetors) and older engines had timing that could not not adjust on the fly.
What all that means is that older engines were delivering a poorer ratio of air to fuel into the combustion chamber, then trying to light that improper mixture with a weak spark delivered in a carbon rich environment and using a static timing set to determine when to fire the plugs regardless of the real time conditions.
So they got worse economy, had less horsepower and ate themselves from within much faster than modern engines which leave virtually no unburned air/fuel mixture after the power cycle.
An older chevy small or big block will deliver just as many miles as a modern LS if they had the same computer controled fuel injection with the same coil pack ignition system and all of the sensors needed to capitalize on those systems; they would deliver 300k regularly just like the modern engines.
And chevy didn't forget how to make camshafts, the government forced engine oil companies to stop using a high zinc content in their motor oil blends; put the zinc back in and the LS camshaft issues disappear
Old engines had a fraction of the spark that modern coil packs provide, older engines had fuel delivery systems that could not adjust on the fly (carburetors) and older engines had timing that could not not adjust on the fly.
What all that means is that older engines were delivering a poorer ratio of air to fuel into the combustion chamber, then trying to light that improper mixture with a weak spark delivered in a carbon rich environment and using a static timing set to determine when to fire the plugs regardless of the real time conditions.
So they got worse economy, had less horsepower and ate themselves from within much faster than modern engines which leave virtually no unburned air/fuel mixture after the power cycle.
An older chevy small or big block will deliver just as many miles as a modern LS if they had the same computer controled fuel injection with the same coil pack ignition system and all of the sensors needed to capitalize on those systems; they would deliver 300k regularly just like the modern engines.
And chevy didn't forget how to make camshafts, the government forced engine oil companies to stop using a high zinc content in their motor oil blends; put the zinc back in and the LS camshaft issues disappear