by Richard Miller » Mon Aug 20, 2018 12:07 pm
The fact that you ask the question tells me that you are aware of the conventional wisdom on this ,, all solid or all rubber ,, the engine torques under load and that has to be transferred to the car somewhere ,, with the diff solid when the engine moves the force is transferred thru the transaxle to the rear mount which is solid ,, supposed to be a NO NO ,,, having said that I imagine most Crown conversions are similar to yours and this is first I have heard anyone mention it ,, shows you are thinking about it ,, my own car is not a Crown and is all rubber so I have no personal experience but I imagine that it must not be a big problem ,, note that in the Crown manual it calls for removing rubber from crossmember at middle location , says it is not stiff enough with rubber there ,, but also says a big block will break the trans case ,, only reason for that to happen is engine moving and trans taking the load ,, my feeling is you are probably okay but it is good you are thinking about it
Richard Miller
West Covina, Ca
'65 V8 Vair