One of the leading names in automotive performance parts, AEM produces aftermarket products designed not only to operate under stressful conditions but also perform better than their stock counterparts. One such performance product from AEM is the performance pulley. AEM performance pulleys claim to increase horsepower by decreasing the parasitic effects that stock pulleys have on the engine. For this purpose, the pulleys are constructed from bullet aluminum, which reduces rotating weight and increases efficiency without affecting emission levels. We got several of these pulleys from AEM and put them to the test.
- Replaces the stock accessory pulleys of the engine
- Lightweight 6061 T-6 billet aluminum construction
- Tooth profile that complies with OEM specifications
- Includes instruction manual, performance belts and decals
- Available in various colors
- Made in the USA
- Significant horsepower boost. AEM states that its performance pulleys can free as much as 15 horsepower from the engine, but it was only half that when we installed the pulley in our cars. It's not that much, but given that this is a component that doesn't require a major overhaul of a car to install, it makes for a considerable plus in our book.
- The pulleys are extremely light yet durable. The pulleys are considerably lighter than their stock counterparts and, after a series of stress and drop tests on our part, just as durable.
- Direct fit installation. Despite its size and aftermarket designation, we had no significant problems installing the AEM performance pulley. In fact, it was as though we were fitting a stock pulley into the engine. OE timing belts also lined up well with the grooves of the pulleys, which we found to be quite an advantage given the difficulty of installing automotive belts in aftermarket pulleys.
- No need to adjust for torsional vibrations. The pulleys are pre-configured, so it is not necessary to adjust for torsional vibration after installation.
- The pulleys may be too big to fit. Some of the performance pulley models offered by AEM are oversized, meaning that they may not fit properly in the engine or even prevent the hood from closing without significant changes. Make sure to check whether the pulleys will fit first before getting one.
The bottom line
Though its oversize models may mean it would not be suitable for all vehicles, the AEM performance pulley does provide a performance boost in terms of horsepower.