The summation of these bolt-on parts was a substantial increase in engine performance and tonality. Baseline power figures showed the R32 produced 218 whp (measure at the front wheels via Haldex switching). The car was now making 244 and the sound coming from the polished tips of the TT exhaust is simply glorious.
For and up-close look at this install, go to www.europeancarweb.com. Get to the "project car" section. We can only say how good it sounds so many times. You've gotta see and hear this thing to believe it.
HRE Wheels
Crystalline Clear
*While your cars wheels may not seem like the most complex component, manufacturing a high quality aftermarket wheel isn't nearly as easy as one may think. Wheels are subjected to complex loading from drive and braking torque, side loading from cornering and radial loads from the car's own weight and magnified by road irregularities.
A good wheel starts on the drawing board, or in this case the CAD program. Each HRE wheel is first designed as a digital model so it can be tested in an FEA (Finite Element Analysis) program that allows HRE's engineers to make sure every wheel is optimized for both strength and weight. Most companies advertise that their wheels are FEA tested, but the complexity of building an accurate digital model is a different story. With over 30 years in the wheel business and using destructive testing on real samples assures HRE is using the best data possible. Not only does digital modeling allow them to maximize the wheels performance, it also allows them to make sure the wheel will bolt on to the car. HRE maintains an exhaustive database of different vehicles dimensions and fitment data. HRE's engineers also work closely with aftermarket brake and suspension manufacturers to ensure no fitment problems will pop up with whatever set-up the customer happens to be running.
Once you have optimized the design, you need to figure out how to build it. You wont find any cast wheels coming out of HRE, they just don't have the required consistency or strength. All the hunks of aluminum coming out of HRE have been forged. The centers start life as a piece of 7-inch billet of 6061 that is mashed into shape with pressure, not heat. Think Play-Doh fun factory just shinier. Forging allows the crystalline grain structure of the Aluminum to orient itself in the direction of the spokes, optimizing strength. The centers are then heated treated to a T6 Temper before being CNC machined entirely in-house.
The rim halves start as sheets of 6061 aluminum that are spun forged on a lathe. Think of a pottery wheel except instead of clay a giant sheet of aluminum that will slice off appendages or entire limbs. The spin forging aligns the structure in circumferential grain to maximize the hoop strength of the rims. Once the spin forging is completed they are brought to the same T6 temper as the halves. The inner mating surfaces of the wheel halves are then machined to make sure they are perfectly flat to match the centers and the holes for the fasteners are then drilled. The bolt-holes have to be incredibly precise for they determine concentricity of the final wheel. A slight mistake in drilling can turn your high-end European sports machine into a Teutonic paint shaker.