Unorthodox Racing Crankshaft Pulley - Underdrive - CCU691

UNLEASH YOUR ENGINES POWER POTENTIAL

UR MAXX Power pulleys mean more HP/TQ over the entire rev-band. The only mod that keeps giving by making your other mods better. Unlimited power gains and better mileage. No other engine bolt-on comes close to offering the HP/TQ gains. This is why UR pulleys should be your “First Mod”

UR = UNLIMITED POWER POTENTIAL

HOW DOES UR DO IT?

By reducing rotational weight which means your engine revs up faster, freeing up HP/TQ for improved acceleration. For some applications we add even more HP/TQ by turning the engine accessories slower, a method called underdriving. Underdriving the accessories (alternator, a/c, power steering & water pump) stops them from robbing more power than they need to run efficiently. When underdriving we tune in the max possible amount without hurting accessory function, we call it “OE SAFE” underdrive. Underdrive crank pulley/sets can add 10-15% more HP/TQ than our stock diameter version. We can also increase HP/TQ gains even more by adding accessory pulley. Accessory pulleys are available in pulley sets or separately (alternator, a/c, idler, power steering, tensioner & water pump). If a crank pulley is your only option don’t worry, if we make accessory pulleys in the future you will be able to add them.

HOW DO I CHOOSE? - Availability of these options varies based on vehicle year, make, model & engine.

First Option: Pulley sets which includes a crankshaft pulley in stock diameter or underdrive and one or more accessory pulleys.

Second Option: Crankshaft pulleys in stock diameter or underdrive. (underdrive is not for use with superchargers or aftermarket/stock audio systems over 600 watts RMS).

Third Option: Accessory pulleys (stock diameter) may be available separately to really “Maxx”imize weight reduction. Say you already have our crank pulley and want to add an alternator, idler, power steering, tensioner or water pump pulley. 

• Most HP/TQ over the entire RPM band.
• Lightest power pulleys available anywhere.
• Most HP/TQ per dollar of any engine bolt-on.
• 23+ years of “real world” use from street to strip to rally to road course.
• 3D engineered and CNC manufactured in the U.S.A.
• Made using only U.S. produced raw materials.

FITMENT