From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Table of interior measurements and clearances for various horsepower models.
| Identifier | ExFiles\Box 127\5\ scan0067 | |
| Date | 7th October 1940 | |
| Em/Wym.{G. Harold Whyman - Experimental Manager}1/SW.7.10.40. - 5 - 8 H.P. 8 Tourer. 8 H.P and 9 H.P. Super. 9 H.P. 10 H.P. 12 H.P. 14 H.P. and 20 H.P. Standard wheel clearance from seat cushion. 7" | 7" | 6" | 6" | 5½" | 5" Steering wheel clearance from seat squab. Max. 18" Min. 12" | Max. 18½" Min. 12½" | Max. 15" Min. 10" | Max. 17" Min. 10" | Max. 15½" Min. 10½" | Max. 15½" Min. 10½" Rear seat knee room. Max. 11" Min. 5" | Max. 11" Min. 5" | Max. 13" Min. 8" | Max. 16" Min. 9" | Max. 17" Min. 12" | Max. 16" Min. 11" Front Seat height. 12" | 12" | 13" | 13½" | 14" | 12" Rear seat height. 12" | 15½" | 16½" | 15½" | 15½" | 16" Squab to clutch pedal. Max. 43" Min. 37" | Max. 43" Min. 37" | Max. 40" Min. 35" | Max. 43" Min. 36" | Max. 40" Min. 35" | Max. 42" Min. 37" Maximum interior height. 46" | 49" | 48" | 49" | 50" | 46½" Front head room. 36" | 39" | 37" | 37" | 37" 39" Deluxe | 37½" Rear head room. 35" | 36" | 34" | 34" 36" Super | 36" Deluxe | 37½" | ||