Top Gear’s Top 9: side exit exhausts

Mad-looking car. Mad-looking exhausts. TVR’s raucous 4.0-litre straight-six was liable to burn the ankles of onlookers, and the fingers of drivers when the savage power overwhelming the rear tyres.

Because each bank of cylinders had its own manifold and exhaust, if you stand by the side of a Viper while it revs, you’re only being treated to the sound of five cylinders, hence why the 8.3-litre Dodge can make a noise curiously akin to an Audi Quattro.

And there you were thinking side-exit pipes were just for show and style. McLaren routed the SLR’s out just aft of the rear wheels  - at great complication and expense – so the car’s flat floor and rear diffuser were not compromised aerodynamically. It was also a nod to the original SLR from the Fifties, which had side pipes, and was repeated for the SLR Stirling Moss roadster, which as you can tell, The Stig is a huge fan of. Just look at that grin.

Nerd point: how can you tell if the Caterham Seven in front of you uses the old K Series engine, or a newer Ford powerplant? Well for one thing, note where the exhaust pokes out. For the Rover engine cars, the passenger gets deafened. On today’s Ford Duratec models, the driver is the one who scolds their shins when clambering in and out.

What’s better than a side-exit exhaust? Yep, two. Now try two on each side for best results. Especially when they’re singing the song of a 390bhp 4.7-litre Ford V8. Only six originals were build in the mid-1960s, and command a multi-million dollar premium when they occasionally pop up for auction.

An SUV does not require side-exit pipes. Vulnerable to off-road clouts, not to mention in prime position for scaring nervous child passengers, they are nonetheless a G-Wagen staple seen of AMG versions since 2004’s G55 AMG.

The street-legal sister car to the lip-bitingly gorgeous D-type, the Jaguar XKSS was a run of only sixteen cars made way back in 1957. 25 were planned, but the remaining nine were lost in a factory fire. Being essentially a road-going Le Mans car, the XKSS’s side pipes ran hot and spat fire, but Jaguar kindly fitted them with a guard plate before unleashing them onto the public highway.

From 1965-67, Chevy had a quality optional extra for the Stringray: an ‘off-road exhaust’ package. That wasn’t an early take on the off-roading supercar, a la Huracan Sterrato: it was ‘off-road’ as in ‘on-track’. Despite costing only $131, it was a rare choice with only one in ten Vette buyers ticking the box.

Wow. Even half a year on, it’s not got any less outrageous, has it? The turbocharged Singer uses side-pipes to steer exhaust gubbins away from its rear diffuser – a packaging nightmare in an arse-engined car. But one we’re very glad Singer went to the trouble of creating.