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).
Comparison of various ignition coils, including Delco and Lucas types, with a focus on reliability and design weaknesses.
| Identifier | ExFiles\Box 168a\4\ img200 | |
| Date | 22th April 1941 | |
| Rm{William Robotham - Chief Engineer}/HC.B/T.22.4.41 - 6 - TYPE CAR WEIGHT DELCO B.80 4 lb. 6 oz. 662NO.2. DELCO B.60 3 lb. 9 oz. DB{Donald Bastow - Suspensions}2012. DELCO B.40 3 lb. 11 oz. 647X. LUCAS Myth 3 lb. 4 oz. DX4A. Vauxhall 10 LUCAS Hillman 10 2 lb. 15 oz. BR54A LUCAS Austin 8 2 lb. 13 oz. RK4A. COILS. We have come to the conclusion that the Lucas "Sports" coil is suitable for all cars. We have two types of Lucas coils in view: (i) The "Sports" coil, and (ii) The "R" type coil. We feel the "Sports" will prove more reliable since it is longer and thus has a longer leakage path. The "Sports" coil has a lower working temperature than the R.R. coil, which should give it greater reliability under adverse conditions. A "Sports" coil has completed 13,500 miles on 1-B-30 and 3200 on the Studebaker, without trouble. There is a weakness in the R.R. coil, in that it is impregnated and filled with paraffine wax. The paraffine wax melts and drains to the bottom of the case under extreme conditions, and not only tends to leave parts of the winding unsealed, with consequent corrosion due to corona effects, but permits, if the manufacturer has not been very careful, movement between primary and secondary, with a resultant breakdown. This can be avoided by | ||