MWR Underdrive Pulley – 1ZZ, 2ZZ Alternator

Free up the horsepower you’re wasting!

MWR’s lightweight aluminum alternator pulley drives your alternator 25% slower than stock to minimize parasitic loss and improve acceleration. By spinning the alternator more slowly you also decrease wear to the ZZ engines’ fragile alternator bearings.

All MWR pulleys are made of lightweight 6061 aluminum with a hard anodized coating. This results is an ultra light part with the same surface hardness as hardened steel. Weight is 160g, compared to 220g for the stock pulley.

Lighter weight. More power. Longer alternator life.

Includes alternator pulley only. Underdrive water pump pulley available separately. Longer belt required – just add 2″ to your stock belt length if upgrading both alternator and water pump pulleys.


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