The acceleration process of a performance car begins when you push the throttle pedal down and ends when the tires apply the power, but there are a few stops in between these two points. One of the last places horsepower passes through is the rearend, as the gears turn the axles via their splines that the tires are attached to. Kip Hayden from Moser Engineering goes over axle spline basics and other items in this informative video from Moser.
The spline of an axle is the teeth or peak that are machined on the end of the axle and mesh with the differential or spool inside the pumpkin of the rearend. All of the power from the driveline is transferred back to the gears that rotate whatever is in contact with the axles, so having the correct spline count that matches the power level being produced is critical. To find out how many splines the axle you want to replace has, just count the individual ridges on the end of the axle, it’s that easy!
There are some significant advantages in going to an aftermarket axle, the first being how much power they can handle. Typically going with an aftermarket axle like what Moser offers will add close to 30-percent more strength than the stock units inside a rearend. For racers, another advantage is the contingency money that Moser offers if you pick up a win while using their products on your racecar. Finally, there is the advantage of having a warranty for the axle you choose.
The Moser Engineering website is packed with information about axles, splines, and more on how to select the right driveline parts for your application.