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Catalytic converter
The so-called 'cat', compulsory in all petrol-engined cars sold in the EU since the 90s, is these days more sophisticated and less intrusive than the power-sapping devices made compulsory in the US in the mid-70s. Early 'cats' also often gave out sulphurous bad-egg smells as an unfortunate by-product.
It's a little gadget in your exhaust system that converts harmful engine gas emissions into more friendly by-products, such as nitrogen, water and carbon dioxide, using metal catalysts.
The so-called 'cat', compulsory in all petrol-engined cars sold in the EU since the 90s, is these days more sophisticated and less intrusive than the power-sapping devices made compulsory in the US in the mid-70s. Early 'cats' also often gave out sulphurous bad-egg smells as an unfortunate by-product.
It's a little gadget in your exhaust system that converts harmful engine gas emissions into more friendly by-products, such as nitrogen, water and carbon dioxide, using metal catalysts.
Monocoque construction
Also known as unibody or unitary construction. Early cars had their bodies bolted on to a separately-built chassis framework, with all the weight supported by the chassis, but a monocoque distributes the load better around the structure. It gives greater rigidity than a body-on-frame structure, thus improved ride comfort, refinement and precise handling, but is not thought to be so rugged: many hardcore 4x4s and pick-ups are still body-on-frame, though most new SUVs and even the latest Range Rover have now shifted to monocoque design.
The first monocoque car was the 1923 Lancia Lambda, but it was the 1934 Citroen Traction Avant that really popularised the concept.
Also known as unibody or unitary construction. Early cars had their bodies bolted on to a separately-built chassis framework, with all the weight supported by the chassis, but a monocoque distributes the load better around the structure. It gives greater rigidity than a body-on-frame structure, thus improved ride comfort, refinement and precise handling, but is not thought to be so rugged: many hardcore 4x4s and pick-ups are still body-on-frame, though most new SUVs and even the latest Range Rover have now shifted to monocoque design.
The first monocoque car was the 1923 Lancia Lambda, but it was the 1934 Citroen Traction Avant that really popularised the concept.
Rack-and-pinion steering
Coming to the masses with the 1934 Citroen Traction Avant, this has now almost entirely supplanted box-type recirculating-ball steering in passenger cars, although the latter remains in many trucks and SUVs, as it is durable and gives less unwanted feedback (important in a heavy vehicle).
Rack and pinion is a simple design, with only two linkage components (the tie rods which connect to each end of the rack) and it allows for greater precision and responsiveness to the driver. A gear-set converts the rotational force from the steering wheel to the force needed to move the steering arms on their spindles and this can be set in a variety of ratios according to the type of car – or even variable ratios according to speed in the same car.
It's the (so far) definitive layout for sheer steering pleasure – even Mercedes-Benz, which hung on to recirculating-box steering long after most had abandoned it, has now finally embraced the rack system in its saloons and estates. Wonder how Mercedes got its reputation for making comfortable but uninspiring-to-drive floaty cruisers? Look no further than the steering set-up of, say, the W123- and W124-series E-Classes.
Coming to the masses with the 1934 Citroen Traction Avant, this has now almost entirely supplanted box-type recirculating-ball steering in passenger cars, although the latter remains in many trucks and SUVs, as it is durable and gives less unwanted feedback (important in a heavy vehicle).
Rack and pinion is a simple design, with only two linkage components (the tie rods which connect to each end of the rack) and it allows for greater precision and responsiveness to the driver. A gear-set converts the rotational force from the steering wheel to the force needed to move the steering arms on their spindles and this can be set in a variety of ratios according to the type of car – or even variable ratios according to speed in the same car.
It's the (so far) definitive layout for sheer steering pleasure – even Mercedes-Benz, which hung on to recirculating-box steering long after most had abandoned it, has now finally embraced the rack system in its saloons and estates. Wonder how Mercedes got its reputation for making comfortable but uninspiring-to-drive floaty cruisers? Look no further than the steering set-up of, say, the W123- and W124-series E-Classes.
Synchromesh clutch/gearbox
Who, racing drivers apart, knows how to double-declutch these days? Before the advent of synchromesh, the driver had to carefully apply the clutch and blip the throttle to make sure the gears were spinning at the same speed as the engine when the clutch was engaged to change gear: get it wrong, and there'd be a hideous grinding noise at best and the risk of breaking or bending the gear teeth and cogs. Hence the term 'crash gearbox'.
But the application of mesh to the gears, enabling only one pair to lock to the transmission shaft at any one time, meant the synchronisation was done automatically. Many race cars have crash boxes, as it's still a quicker gear-change process and they'll have their transmissions rebuilt between events anyway, but for the rest of us, it makes for far simpler, quieter and refined progress.
Cadillac was first in 1929 with a synchronized system, but the design was developed by Porsche for the 356 (1952). Most mainstream cars did without synchromesh on first gear until well into the 60s, though.
Who, racing drivers apart, knows how to double-declutch these days? Before the advent of synchromesh, the driver had to carefully apply the clutch and blip the throttle to make sure the gears were spinning at the same speed as the engine when the clutch was engaged to change gear: get it wrong, and there'd be a hideous grinding noise at best and the risk of breaking or bending the gear teeth and cogs. Hence the term 'crash gearbox'.
But the application of mesh to the gears, enabling only one pair to lock to the transmission shaft at any one time, meant the synchronisation was done automatically. Many race cars have crash boxes, as it's still a quicker gear-change process and they'll have their transmissions rebuilt between events anyway, but for the rest of us, it makes for far simpler, quieter and refined progress.
Cadillac was first in 1929 with a synchronized system, but the design was developed by Porsche for the 356 (1952). Most mainstream cars did without synchromesh on first gear until well into the 60s, though.
Disc brakes
Essentially a system whereby discs attached to the wheel hubs are gripped by calipers with pads either side, slowing or stopping wheel rotation.
Disc brakes proved their worth immediately when the Jaguar C-Type, the first racing car to feature this design, won in spectacular fashion at Le Mans in 1953, as the C-Type could corner quicker and more accurately than anything else on the circuit.
Disc brakes are more resistant to fading than drum brakes, can handle higher forces and are simpler to maintain, altogether significantly increasing stopping power. They are now standard on the vast majority of cars, at least at the front (drum brakes remain cheaper to manufacture).
Essentially a system whereby discs attached to the wheel hubs are gripped by calipers with pads either side, slowing or stopping wheel rotation.
Disc brakes proved their worth immediately when the Jaguar C-Type, the first racing car to feature this design, won in spectacular fashion at Le Mans in 1953, as the C-Type could corner quicker and more accurately than anything else on the circuit.
Disc brakes are more resistant to fading than drum brakes, can handle higher forces and are simpler to maintain, altogether significantly increasing stopping power. They are now standard on the vast majority of cars, at least at the front (drum brakes remain cheaper to manufacture).
Reversing light
Another one for the so-obvious-it-hurts list: a white light to show other road-users that you have selected reverse gear. And that you might wish to go backwards at some point.
Shame it's almost universally ignored by most rush-hour rat-runners down residential streets, who fail to realise that the locals might actually want to park their cars near their houses, then hit the horn. Grrr.
Another one for the so-obvious-it-hurts list: a white light to show other road-users that you have selected reverse gear. And that you might wish to go backwards at some point.
Shame it's almost universally ignored by most rush-hour rat-runners down residential streets, who fail to realise that the locals might actually want to park their cars near their houses, then hit the horn. Grrr.
