Actively exhausting

Who now remembers basso profundo Triumph TR2s? At about 2,400rpm, as I recall, they made a deep crisp booming noise which, if you got it to coincide with a low bridge or a long retaining wall reverberated beautifully. You can scarcely imagine Canley engineers solemnly conspiring to provide it – maybe they did – but it was always tempting to accelerate in second or third gear to achieve the delightful crackle. This, you felt, was a sports car. Anybody overhearing must love it.
Well, they probably didn’t. They probably thought it was just a noisy car but aged 19 or 20 it didn’t occur to you that anybody could dislike it. They might as well not like Beethoven. Or the Beatles. TR2s weren’t very fast; 0 to 60 in 11sec and 105 or so mph, but they felt fast.One TR I knew well, (left) Ian Brown’s, OVD 888 on a Scottish Rally.
It’s different now. I don’t like noisy cars as much, but I have to make an exception for the F-type Jaguar. Engines nowadays are so muffled and de-toxed that crisp crackling exhausts are pretty well outlawed. The racket that thrills motor race spectators has been muted, so in an almost wholly successful effort to restore what was regarded as an essential feature of a sports car, Jaguar has what it calls an active exhaust system. Electronically controlled valves in it open to what Autocar described as their angry position, under hard acceleration or when the driver selects Dynamic on the touchscreen. A satanic roar, the testers said, at 4500rpm and a very lovely scream between 5000rpm and the red line.

Jaguar F-type. Silent when stopped.

Active Exhaust is reinventing what young “scorchers” had in the 1920s. Cut-outs enabled drivers to by-pass silencers at the touch of a switch or a lever, reducing back-pressure and squeezing out a few more precious horsepower for overtaking. Or simply making more noise. Jaguar doesn’t claim any extra bhp from “active” exhausts but it sounds magnificent. And you don’t need a low bridge to get the best out of it. TR2 rev counter on the right