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).
Blueprint showing the best tested arrangement for a 20/25 HP silencer.
| Identifier | ExFiles\Box 104\2\ scan0023 | |
| Date | 30th May 1932 | |
| 20/25 H.P. SILENCER BEST ARRANGEMENT YET TESTED BAFFLE DRILLED AS BAFFLES AT REAR BUT WITH CENTRAL HOLE FILLED IN CENTRE TUBE NOT DRILLED OVER THIS LENGTH BLANK BAFFLES PIPE OPEN AT END. P.II SHORT TYPE SILENCER WITH REGARD TO LENGTH AND DIAM. P.II CUT OUT TUBE SHORTENED TO SUIT. PIECES SHOWN IN DOTTED ARE DRILLED. STANDARD DIAMETER DOWNTAKE PIPE, BUT NO FRONT EXPANSION BOX. STANDARD DIAMETER FISH TAIL PIPE, BUT NO FISH TAIL. CENTRAL PIPE DRILLING:- 8 ROWS OF 5/16 DIAM HOLES, HOLES 1" SPACING, TO THE REAR OF THE LAST BAFFLE THIS DRILLING IS DOUBLED I.E. 16 ROWS 5/16 HOLES 1" SPACING. BAFFLE DRILLING:- AS ATTACHED SKETCH. | ||