It's a little hard to see...
It's a little hard to see from this angle, but trust us when we tell you that AFCO machined lightening pockets inside the caliper for maximum weight reduction without sacrificing rigidity.
Stainless steel is used in the internal components, such as the abutment plates (which reflect heat and protect the caliper from pad gouging), the heat shields (which reflect heat from the caliper helping to reduce fluid temperatures), and the pistons (which further reduces fluid temperature as well as piston wear). The exclusive interlocking design significantly reduces caliper flex and distortion. This extra rigidity provides for more consistent stopping performance, less brake pad taper, and less brake pedal effort. You'll remember in Circle Track's "Brake System Checklist" (Feb. '09), Bob Bolles discussed how critical pad taper or minimizing it is to having a properly functioning system.
These four piston calipers also feature stainless steel pistons that help reduce fluid temperature and piston wear.
Keep in mind that while the weight of the calipers is important, it won't affect the rotating weight of the wheel assembly because they are mounted to the chassis. So our final weight comparisons do not include caliper weight.
Wheels Our final piece of the puzzle is a new set of wheels. Weld Racing recently introduced a new design for its left-side rear racing wheels (see Circle Track's Sep. '08 "Quick Tech"). The XL Series Dirt Late Model racing wheels feature a design that incorporates a dzus-on mudcover without having to run a beadlock. The LR wheel (PN 559-5465) also boasts an inside beadlock. While that in itself is not unique, the engineers at Weld reworked the inner rim half in order to maximize clearance using the largest brake packages available in today's racing market as their guide. The result is a wheel that will clear any brake caliper out there.
Excess space is very important but we're talking about weight savings in this article. Weld offers these features on two types of wheels, the XL and HS. The XL stands for Extra Light, while the HS is, not surprisingly, the High Strength version. By going with the XL, we were able to trim 3.4 pounds from each one of our wheels which will help us keep the overall weight of the assembly to a minimum.
The Bottom Line Or should we say, why is this exercise so important? Here's the bottom line: rotating weight. The concept of rotating weight has been applied to numerous components in a race car, from crankshafts to driveshafts (can you say carbon fiber?) to wheels. By swapping out the components that we did on Project DLM, we were able to lower the overall weight by 30 pounds. That's significant because any time you can reduce rotating weight on something, you're going to free up power. Without getting overly technical, our original wheel assembly required a certain amount of energy (read horsepower) to make it turn or rotate. By lightening the weight of the assembly, we reduced the amount of power needed to turn it. That's power which, theoretically, can be applied somewhere else, preferably to the track if the setup is correct and working well.
A word of caution, cutting weight for the sake of cutting weight is not the answer. You must always remember that when you trim weight you have the potential to sacrifice strength. Be very careful in any process where you are trying to trim weight, always research the strength and rigidity of the product for the specific application.
Weld's XL Series Dirt Late Model racing wheel combine a reduced weight with superior strength, which fits perfectly with our goal of creating a lightweight wheel assembly.
A bonus of choosing the XL from Weld is its inside beadlock wheel has been designed to accommodate the biggest calipers and rotors on the market.