More Power to the Ground

Independent testing by a leading automotive magazine (Turbo, October, 1996) showed rear wheel horsepower gains of more than 5% with the simple switch to an ACPT carbon fiber driveshaft. This significant increase is primarily due to lower rotational mass of the driveshaft. Carbon fiber offers you more strength to resist extreme torque than steel with about half the weight. Just like the common use of lightweight clutch and flywheel units, a lightweight driveshaft allows more of you engine's power to be applied to the ground.

In addition to minimizing rotational power losses, carbon fiber's unique vibration dampening characteristics also help improve power output. Engine builder's are familiar with the power gains that high performance crank dampeners can provide. ACPT's carbon fiber driveshafts give you similar benefits by cutting power losses due to drivetrain vibration.

Higher RPM, Faster

Driveline vibration is a common problem that can limit RPM. ACPT's involvement in racing began in 1986 when Dan Gurney asked us to apply our long time expertise in aerospace composites to solve a vibration problem with his IMSA GTO Toyota Celica. In this front engine, rear transaxle race car, the driveshaft ran at engine speed. The metal driveshaft was experiencing harmonic whip limiting usable RPM and forcing them to run the engine well below redline in each gear. ACPT developed a carbon fiber driveshaft that allowed a 1000 RPM increase in usuable engine speed and gave the engine a chance to work at its' power peak. Gurney cited the ACPT driveshaft as a major factor in winning the 1987 IMSA GTO Championship. Since 1987 many racers in all areas of motorsports have discovered the extra RPM and the resulting tuning flexibility carbon fiber driveshafts provide.

To Finish First, First You Have to Finish

All driveshafts twist to some degree when torque is applied. The resistance to this twist is measured as torsional spring rate. Standard ACPT driveshafts have a torsional spring rate a little less than aluminum and about half that of steel. The advantage of a lower spring rate is less driveline shock and a reduction of stress on other drivetrain components Every part of your drivetrain may benefit from the use of a carbon fiber shaft.

The continual twist when torque is applied eventually causes all metal shafts to take a set in the twisted position. Consequently the shaft ends become permanently out of phase by several degrees and vibration begins to break components Carbon fiber, on the other hand, has a near perfect "elastic memory". ACPT's carbon fiber driveshafts can't fail by becoming permanently twisted.

As RPM goes up, all driveshafts begin to whip. At a certain "critical speed", unique to each type of driveshaft, this bending of the shaft creates lateral runout and vibration. The intensity (magnitude) and frequency of these bad vibes are determined by a combination of stiffness, density, size, and geometry. This vibration is a primary cause of drivetrain breakage from the transmission to the rear end. The "critical speed" of ACPT's carbon fiber shafts is much higher than steel or aluminum shafts of the same size. Exceptional harmonic damping, (2 to 10 times faster than metal) coupled with high lateral stiffness and low density allow carbon fiber driveshafts to virtually eliminate vibration problems from shaft whip.

Dramatically Improve Safety

In addition to performance advantages, ACPT carbon fiber driveshafts provide a special measure of extra safety. Despite safety hardware like shaft hoops and covers, a broken metal driveshaft can become a flailing bludgeon that beats up everything in its' path; severe injuries to the driver, extreme damage to the car, and even vaulting the car into the air can be the result. Carbon fiber minimizes these dire consequences.

Carbon fiber driveshafts are built for strength primarily to transfer torque and can be broken with a hard blow from the side. The result is that when a u-joint or yoke fails the carbon fiber composite begins to disintegrate when it contacts the chassis. As the composite comes apart, the shaft simply turns into a bunch of loose carbon fibers. much like the end of a broom . In fact, in composite technology this failsafe state is called "brooming". Instead of tearing up the driver and shredding the chassis, the carbon fiber broom will probably just polish dirt and paint off the chassis.

Racers race to go fast, not to cheat death and disability. ACPT is very proud of the fact that our driveshafts have helped to prevent serious injury on several teams, like Dick Anderson Racing. "I have two talented, young drivers to protect," Dick Anderson explains. "Both have narrowly escaped serious injury when metal shafts broke and penetrated their cars. Last season, a bracket came loose, destroyed the torque arm and broke the ACPT shaft in two; but it never came into the car. It "broomed", just as they said it would, and no one was hurt."

Carbon Fiber Isn't Just for Race Cars

ACPT carbon fiber driveshafts are an obvious advantage on the race track; but they also provide the same benefits on the street in cars and trucks as well as in industrial applications. Many cars, pickups, and vans experience vibration problems and performance limitations with OE metal driveshafts, especially two-piece units. Dealers and mechanics around the world are discovering that the only sure way to cure these problems is to install a one-piece driveshaft from ACPT.

An 80,000 Pound Trash Truck With Bad Vibes

Try to imagine the worst possible environment in which to test these driveshafts. How about a trash truck? Continuously starting and stopping hundreds of times all day long, these behemoths can get up to 80,000 pounds fully loaded! Plus, some of these monsters can really vibrate, After running a one-piece, 114" ACPT driveshaft constantly since August, 1994, Greg Hicks, of Central Texas Refuse is positively stoked (racer talk for "I'm REALLY happy.") "The vibration was completely eliminated after installation," Hicks said, "and, we certainly don't baby it."

Mr. Hicks is thoroughly convinced that better all around performance, higher profitability, and lower maintenance costs can be realized by replacing two-piece steel shafts with one-piece composite shafts. Bulk haulers will also enjoy the extra cargo volume and higher profits on every load that light weight carbon fiber provides. ACPT carbon fiber shafts have passed the extensive durability tests of several major Class 8 (tractor/trailer) truck builders and are in customer tanker fleets for highway testing.

Greg Frick, owner of Inland Empire Driveline Service, sees terrific potential for the driveshafts in heavy-weight rigs. "The success at Central Texas Refuse proved it. The only worse scenario might be a concrete hauler and we're working on that now. If you're operating a large fleet of trucks, these driveshafts could make a big difference for you."

A Heavy Duty Industrial Problem Solver

Heavy duty industrial applications, such as pump shafts and cooling tower driveshafts also suffer from the same kind of vibration, critical speed, and reliability problems that are seen in vehicles. ACPT carbon fiber composite shafts are solving problems and improving efficiency while lowering maintenance and repair costs in industrial plants around the world.

Take Advantage of the Experts in Composite Technology

Since its' founding in the seventies by Dr. James C. Leslie, Advanced Composite Products and Technology has been a recognized leader in the research and development of composite components for industrial and defense applications, ACPT is frequently called in to consult on problem solving at other composite manufacturers. You too can depend on ACPT.

Having built custom composite shafts for the world's most elite race teams since 1986, ACPT now offers the carbon fiber advantage for every racer, Call your favorite driveline shop, or ACPT direct, today and get the competitive edge of carbon fiber composite technology.