The O-type and P-type were developed by Lea-Francis from 1927 using a new chassis designed by Van Eugen and having semi-elliptic springs at the front and the rear. This chassis was adapted for use in many of the next Lea-Francis cars. A Meadows 4ED 1496cc engine was fitted, available in single carburettor 38bhp form (P-type) or twin 52bhp form for the O-type. Around 55 O-types and 1093 P-types were made. A derivative was the S-type (or 'Hyper') which used the P-type chassis but placed the Meadows 4ED engine with further back to make room for a Cozette supercharger in front with a 'standard' top speed of 85mph, or 100mph in tuned form. The S-type was the first production Supercharged car sold in Britain. Around 180 S-types were made.