English Electric Engines (Classes 20 and 40)

[Inversnecky]

Watching some YT videos of Class 20s, it struck me how similar the sound of the EE SVT engines was to that of Class 40s, yet while 40s were graced with the nickname of ‘Whistlers’, 20s were ‘choppers’.

I dare say the 20 here is giving a pretty good imitation of a ‘whistling’ 40! Could you tell the difference if you were listening to sound only?

 

[Cheshire Scot]

Watching some YT videos of Class 20s, it struck me how similar the sound of the EE SVT engines was to that of Class 40s, yet while 40s were graced with the nickname of ‘Whistlers’, 20s were ‘choppers’.

I dare say the 20 here is giving a pretty good imitation of a ‘whistling’ 40! Could you tell the difference if you were listening to sound only?

Whilst I'll admit I haven't heard either for quite a number of years was the class 20 perhaps a slightly higher pitch than the 40?

 

[Peter Sarf]

A 20 was the same engine but with half the cylinders (16 vs 8). So I recall they were similar but a 40 always seemed rather louder when nearby.

 

[Cowley]

A very similar turbo set up (although only two on a class 20 vs 4 on a 40), these were SVT engines I believe.
Later EE engines were charge cooled - CSVT (classes 37 and 50 for example) and had a different turbo sound to the earlier engines, more pronounced as they built up revs but quieter on tick over.

 

[Strathclyder]

A very similar turbo set up (although only two on a class 20 vs 4 on a 40), these were SVT engines I believe.
Later EE engines were charge cooled - CSVT (classes 37 and 50 for example) and had a different turbo sound to the earlier engines, more pronounced as they built up revs but quieter on tick over.

Indeed, both have/had Napier turbos, hence the similarities in sound between the 20s & 40s when idling. Worth mentioning here that the Bulleid prototype trio (10201-203; aka Class D16/2) had the same basic engine/turbo as the 40s (the LMS twins had different turbochargers).

 

[Pigeon]

40 is a 20 with the chorus button on.

 

[Strathclyder]

40 is a 20 with the chorus button on.

I've always thought of a 40 as being a 20 with a full backing orchestra.