More on engine soft mounts. I suggest you also consult your engine's instructions. I also have this TF P-51 (in B version) and am installing a ZDZ Super 80. As another reference point, the ZDZ instructions say this:
The engine can be mounted directly to the firewall or to an engine box which is conically changing its shape gradually from engine to firewall. Non-symetric solutions of box helps to decrease vibration level. IN ANY CASE soft rubber spacers or soft silent blocks should not be used. This solution can cause damage to the engine and bearings by providing even higher vibration levels.
Having a mechanical engineering background, this does make sense for single cylinder lightweight high performance engines that have little mass to stabilize itself...like our engines. A rigid mount allows for proper and consistent transfer of torque to the propellor shaft. Yes, soft mounts would offer damping, but could become out of phase with the engine torque pulses potentially causing increased inertial load on the shaft, shaft bearings and connecting rod bearings.
For gas engines mounted on a wood box or aluminum extensions, these already offer slight damping without impacting engine operation/performance. If you ensure proper balancing of your spinner and prop, and soft mount your electronic ignition module & Rx, you should be fine.
Cheers,
Last edited by JDjetjock; 02-09-2014 at 12:04 PM.