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Why Your 986/987/996/997 Needs an Underdrive Pulley

Porsche left some performance on the table when they built the M96 engine in your sports car. With a large diameter crankshaft pulley, your engine is constantly working overtime to spin the air conditioning compressor, alternator, water pump, and power steering pump to higher speeds than they really require. Each of these accessories requires horsepower to spin them, and if you could slow them down, even a little, your engine would be able to send that power to the drive wheels instead. With an EBS Racing 'underdrive' crankshaft pulley, you can do just that.

Possibly the simplest way to free up some horsepower from your Porsche's watercooled flat six engine is by 'underdriving' your engine's accessories. Wether for street or track use, you'll notice an improvement in throttle response, and your engine will rev more freely with this simple modification. This smaller diameter crankshaft pulley fits in place of the larger factory unit with zero further modifications necessary, and comes with the correctly sized belt you'll need. This is a simple modification that you can do at home, or drop off to your favorite independent Porsche shop to have this task completed easily.

If you are planning to take your Porsche to the track, or if you frequently visit the upper limits of your engine's rev range, this underdrive pulley can also prevent your air conditioning pump or power steering pump from being spun too quickly, preventing undue stress and wear. The power steering pump is particularly vulnerable to such issues, and can develop an expensive leak from being spun too quickly. The cost of this pulley and belt is far less than the cost of replacing your steering pump, you can trust us on that one.

The pulley itself is precision machined from aircraft-grade aluminum to have the correct metric-style v-belt grooves. Lightweight aluminum construction of the pulley saves rotational mass over the OEM piece, giving back even more lost power. The pulley also features a beautiful black anodized finish to not only make your engine look better, but also to protect against corrosion to keep it looking that way for decades. We're so sure of the quality of this pulley that it's also been given a 2-year manufacturer warranty, so you can rest easy knowing this is top quality.

This underdrive pully is guaranteed to work with any M96-powered Porsche Boxster, Cayman, or 911 built between 1997 and 2008. This product is not compatible with Mezger engined cars (911 Turbo, GT3, or GT2) or 9A1 engined cars (Direct Fuel Injection engines from 2008 onward). For more information on product benefits or fitment, or to place an order, call one of our EBS Racing Porsche specialists at 1-800-462-3774. To see more photographs or to process your order online, you can visit the product page on EBSRacing.com.