Yesterday, in celebration of SEMA, we asked you for the worst auto aftermarket add-on. Today, we'll flip it around and ask you what's the best. Simple. In our mind, nothing beats a bolt-on Roots-type supercharger. Just look at the efficiency map above if you're even for a moment thinking anything else beats it at making your car better. You have something better? Try us in the comments below. (QOTD is your chance to answer the day's most pressing automotive questions and experience the opinions....
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