Metallurgy 101: Mag cases vice Alu
#16
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The mag problems with the mid 70s engines was also heat related. The quick fix of running the engine hotter in the 75 thru 77 engines to pass emissions was not good engineering. The 5 blade fan rather than the 11 blade fan and the thermal exhaust units not only reduced emissions but engine life. It was the kool aid that gave a pretty good car a bad name and a short life. However, like a cat with more than one life, the Eruos are now after these cars. Unfortunately for us in the US, the case machine work, head work, and Maule pistons and cyls is about what the caris worth.