Theoretically this works, but in all reality, if you put a plus three 225/35-18 tire on a Golf, the sidewalls will look tiny. A much better tire selection for an 18-inch wheel on a VW is 225/40-18, which has an overall diameter of 33.94-inches. Increasing the aspect ratio like this will increase the overall diameter of the wheel and throw off the speedometer slightly, but not by much. Another thing to consider is that although the 225/35-18 may be what plus sizing dictates, that size may not be available, or if it is available, it may cost significantly more than a more common 225/40-18 size.
Plus sizing will help you get in the ballpark for what size tire you need, but remember, although the tire may mathematically work out, that specific tire size may not even be produced. With the European tuning scene blowing up the way it is, one of the best methods of deciding a tire size is finding someone else with the same car and size tires you want. Ask them if they are having any rubbing issues and how the car feels on the road. If, however, you're pioneering new tire sizing on a specific car, we recommend giving someone like BFG a call to get a professional opinion.
Source: BFGoodrich, 877/BFG-Tire, www.bfgoodrichtires.com
The Magic Of Forged WheelsForging is one of the most expensive methods of producing a wheel. Despite the cost to both the manufacturer and the consumer, when you consider that forged wheels are generally lighter and stronger than cast wheels, it is no wonder why forged wheels have become the choice product for racing teams, and the prized purchase for many a car owner. What makes forged wheels so expensive and good? The answer is all in the manufacturing process.
First of all, there is no single "correct" way to make a wheel. Every manufacturer has developed a method that works for them, and each manufacturer steadfastly insists that their method is the best. But, when you look at the individual manufacturing techniques used to create forged wheels, they all have several basic components.
The forging process starts similar to the casting process, with a single block of solid aluminum. Unlike casting, where the aluminum is melted into a liquid thus losing minerals vital to the rigidity of the metal, forging only heats the aluminum block into a semi-solid state, allowing the metal to retain its natural chemical makeup. Once the metal is in its semi-solid state, the aluminum block is then placed inside a giant press, and the block is squeezed into the shape of a wheel. This squeezing process varies in pressure, depending on the manufacturer, and each manufacturer insists that its pressure is the ideal amount. For instance, Weld Wheels applies its EVO wheel line to over eight million pounds of pressure, where as Carriage Works, a motorcycle wheel manufacturer, applies over 10 million pounds of pressure. Either way, a lot of pressure is applied.
No matter how much pressure is applied, the idea remains the same: By pressing the block of aluminum with massive amounts of force, imperfections-such as air pockets-will be removed from the aluminum. The more imperfections that are present in a wheel, the more susceptible the wheel is to fatigue. During the forging process, however, the grain of the aluminum block changes. Forged wheels tend to have a radial grain, true billet wheels usually have a straight grain, and cast wheels have little to no specific grain direction at all. Fikse, along with almost every other forged wheel manufacturer, claims that a radial grain is the strongest type of structure for a wheel.
Many wheel manufacturers, such as Fikse, forge the wheel center and use an aluminum rim for the outside portion of the wheel. The aluminum rim is then either welded or bolted to the forged center. There are, however, manufacturers that create entire one-piece forged wheels by either pressing an entire wheel or machining the wheel out of a forged block of aluminum, Weld Wheels uses this process.