The two previous Ford car lines, Standard and De Luxe, had blossomed into three, Special, De Luxe, and Super De Luxe. Ford vehicles had been V8-only since 1935, but dealer requests for an "economy" engine option prompted the introduction of a six cylinder unit. The entry-level 136 CID (2.2 L) V8 was switched in favor of a new 226 CID (3.7 L) L-head straight-6, the first Ford six since the 1906 Model K. The popular 221 CID (3.6 L) V8 remained as the top-line engine and was standard in De Luxe models. Both engines were rated at 90 hp. The 239 CID engine, introduced in 1939 for Mercury and trucks, was continued in the Mercury models. The chassis was longer, with a 114-in (2.9-m) wheelbase.