Is there any concerns with harmonics and crankshaft bearing wear due to the lighter or under drive crankshaft pulley. I am concerned about causing premature wear on the engine for minimal gains.
That shouldn't be an issue, the pulley is machine balanced. Actually, less rotational mass means less work for the engine. Less work means less wear.
Although I am hesitant to do a lot of modding, the pulley swap and the wheel spacers both make the most impact for the price.
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