The Alvis 4.3-litre and Alvis Speed 25 were British luxury touring cars announced in August 1936 and made until 1940 by Alvis Car and Engineering Company in Coventry. They replaced the Alvis Speed 20 2.8-litre and 3.5-litre.
New engines
The Speed Twenty’s 2.5-litre, 2.8-litre or 3.5-litre engines with four main bearings were replaced in the 4.3-litre and 3.5-litre Speed Twenty-Five with a strengthened newly designed six-cylinder in-line unit now with seven main bearings.
Chassis
The leaf springs at the rear were 15 in longer than on the previous model. The brakes had servo assistance.[1]
Coachwork
Alvis did not make any of the bodies for the Speed 25. The cars were supplied in chassis form and firms such as Cross & Ellis (standard tourer) Charlesworth (standard saloon and Drop Head Coupé) as well as Vanden Plas