WHEELS 101

 UPGRADING YOUR CAR'S WHEELS IS ONE OF THE SIMPLEST IMPROVE LOOKS AND PERFORMANCE, BUT DO YOUR HOMEWORK FIRST

RIMS, mags, hose reels, steelies-whatever you call wheels, we wouldn't get far without 'em! The term 'mags' is actually an old one used to describe lightweight racing wheels made out of magnesium alloy, but it has come to apply to any aftermarket rim.

They don't use magnesium in wheel production anymore. Instead, wheels are generally made out of pressed or stamped steel or aluminium alloy, or, in rare cases, carbonfibre. Steel wheels are cheaper and heavier but are capable of handling heavier weights and bigger hits compared to aluminium, while aluminium or carbonfibre reduces unsprung weight, and this improves handling as well as braking and accelerative performance.

Most cheaper alloy wheels are cast, which involves molten metal being poured into a mould, while more expensive rims are forged or machined from a billet of metal. The higher cost of manufacturing forged and billet wheels makes them more expensive than cast items, but they also offer a stronger, higher-quality finish.

Wheels are sometimes advertised as single-piece, two-piece or three-piece, and this refers to modular construction. Most off-the-shelf wheels will be singlepiece, where the face of the wheel, lip and barrel are all made in one solid unit, which helps keep costs down by allowing easier mass manufacturing.

Two-piece wheels allow more customisation, including unique offsets, because the centre of the wheel is welded into the barrel to the customer's specs. Threepiece wheels are even more customisable, as the wheel centre, barrel and outer lip are all separate pieces able to be mixed and matched.

Now that we've covered the basics of construction, let's go over the terms you'll need to understand in order to successfully measure your old rims and spec your new ones.

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