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).
Investigation into throat areas on high power cylinder heads to explain performance differences.
Identifier | ExFiles\Box 134\2\ scan0099 | |
Date | 8th December 1936 | |
To Rm.{William Robotham - Chief Engineer} Copy to Da.{Bernard Day - Chassis Design} Rm{William Robotham - Chief Engineer}/Edwards. E/PSN.1/MN.8.12.36. 1129 Throat Areas on High Power Heads. We send you herewith a print of LeC.5422 showing the throat areas on the various overhead inlet and side exhaust valve cylinder heads. No.1 and no.2 heads are to the same drawing but owing to their difference in performance the throat areas were investigated as a possible cause. It will be seen that there is only approximately 5% difference in the throat areas which hardly seems sufficient to explain the difference in performance of the two heads. The effect of throat area on performance is to be investigated by opening up the throat of No.1 head as indicated, to increase its throat area by 20%. It will also be noted that the throat area of the inclined inlet valve head is about 50% greater than that of the original head. The throat areas on both types of head are limited by the existing stud positions. These positions are not fundamental and could be moved out to increase the throat area on a future design if this is found to be desirable. Before opening out the throat area on the No.2 head, the performance of both Nos.1 and 2 heads is to be checked, as arranged by Rm{William Robotham - Chief Engineer}/Edwards. E/PSN Att:Print of LeC.5422. | ||