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).
Phantom II rear wheel arch clearances, addressing brake drum and various tyre fitment issues.
| Identifier | ExFiles\Box 14\8\ Scan202 | |
| Date | 2nd January 1930 | |
| x7380 S/s (BY.{R.W. Bailey - Chief Engineer}) Copy to Sg.{Arthur F. Sidgreaves - MD} " " Hs.{Lord Ernest Hives - Chair} " " AZ. " " JLE.{J. Lee Evans - Chassis Test Manager} (Struck through) " " HO. Ev{Ivan Evernden - coachwork}5/EEN2.1.30 PHANTOM II REAR WHEEL ARCH CLEARANCES We have discussed the problem with Sg.{Arthur F. Sidgreaves - MD} who is writing to you. The issue contains two parts (1) The question of brake drum clearances, and we think it is now agreed these should go through as indicated on N.Sch.3003 and the accompanying letter. You will no doubt arrange for subframes to be altered at Derby, and those likely in stock at Coachbuilders. It will be understood that we do not wish any bodies to be modified except those which can be attended to without any cost to ourselves. The second part of the issue is that of the clearances for the tyres. You will see from Sg{Arthur F. Sidgreaves - MD}'s memo. that we are now giving Customers the option of the Silent Tread and the Buttress Tread, the latter is slightly the fatter. It is our experience that the clearances as shown are only just adequate, and what we wish to do is to make them ample for these tyres;and just possible for the Fort Dunlop, the India, and the Goodrich. We do not propose telling the Coachbuilders that we are making the clearances just possible for these tyres but we do want to feel sure that should an Owner at some subsequent date either through necessity or choice wish to have these fitted he will not get serious fouling of the tyre against the side of the wheel arch. In N.Sch.3003 we have shown the width of the top of the wheel arch reduced by 1". As suggested in conversation with you over the 'phone we would be glad if you would see whether we could manage to do with the reduction of only ½". If you would kindly set out the Buttress Tread and the Silent Tread Dunlop on the wheel in the bump position as shown with the 4⅞" dimension and then sketch in the India and Fort tyre we think you will see whether this dimension is feasible. We do not mind if the India and Fort tyre practically run say ¼" clear; but we want at least ⅝" clearance between the side of the arch and the tyre in the case of the Silent Tread and Buttress Tread. We leave you to decide whether we can have this 4⅞" dimension, or whether we must go to the 4?". With reference to the new proposed wheels (20" rims) we do not think they affect the issue as we still have to go on building cars in the intervening period. Bodies built to these revised clearances will certainly suit the new tyres and rims as these wheels will be a little smaller although from the dimensions given to us there will be very little | ||