[Greg Reimer 7376]

Back in the bad days of 1973-77,I worked in a few Chevy dealers,doctoring the worst cars ever built in this country when they were new, and the thing that happened a lot were valve guide and valve train failures. Seats used to disappear, guides went away a lot, camshafts went flat a lot, and it was a mess. Everybody blamed the new lead free fuels for it, and the valve face and seat erosion seemed to reflect that. Also, when you run a motor with about 22 degrees total timing and with a cam that is ground late like all those were, exhaust temperature was through the roof. Here's the good question--why didn't all those engines do that since they were operated on the same fuel?As far as the guide wear, the SBC used to shove the valve sideways as it was opening it. That would indicate side loading caused by improper rocker arm and valve train geometry.Since these were mass produced,union labor assembled engines on an assembly line with a broad range of production line tolerances, some obviously had the valve train geometry right on the money, some probably weren't even close.The comment of the extra torque needed to rotate an engine with valve train issues seemed to point that out. Stock eliminator motors are an exercise in mechanical refinement,from wall texture and accuracy, ring seal, compression, and the valve train. Add it all together right, you've got a winner. Those new cars made in that time frame were all losers for the most part.