Motor mounts - soft versus hard

[Alec]

When we installed our 427w the engine seemed very high in the bay, and the difference btw the pinion angle and the driveshaft angle was north of 4 degrees without shims. Shimming up the tail 2" or more brought the angles closer but also brought the shift lever up pretty high. I decided to go with hard mounts to bring the motor down in the bay AND reduce the downslpe of the tail. All is good now regarding the angles (less than 2 degrees of difference, with 3/4" of shims) and the shift knob height, and the motor sits lower and shouldn't hit the hood. I'm wondering people's experience with the FFR rubber motor mounts versus the Levy hard mounts. Does it make a huge difference in vibration transfer? Are there any in-between (e.g. poly) mounts available if the vibration is bad once we get it on the road?

[cc2Arider]

I'm also interested in the opinions about this because I spec'ed a Pro-Flo4 on my 427w, and I understand the installed height to the hood is pretty tight...
@FMan used solid mounts in his build to bring the height down, and I plan something similar.

Craig C

[edwardb]

I can't comment about soft versus hard. But FFR doesn't supply rubber motor mounts as the original post suggests. They provide Energy Suspension poly mounts for the engine and trans. A donor build may use the original Ford rubber mounts, I don't know. But if so, wouldn't have come from Factory Rive.

[John Ibele]

I have a different engine (small block based) but went through this decision a while back. I started down the path of solid mounts based on a vendor recommendation. I began questioning that choice when I realized that it put my oil pan 1/2" below the frame. For many that's not seen as a killer issue, but I couldn't get comfortable with it and ended up reverting to the kit-provided poly mounts. In going through that process I read plenty about 'never using solid mounts on a street vehicle' ... but heck, we're building a car which, under any circumstances, is going to be considered a very firm ride. If the solid mounts had solved a clearance problem rather than created one for me, I would have gladly used them.

[Norm B]

The difference in vibration transfer between the various types of engine mounts will be hardly noticeable while driving but, when the car isn’t moving and the engine is idling the difference can be profound. If you have a performance camshaft with lumpy idle characteristics it could get a little annoying sitting at a stop light. Everything shakes.

Norm

[Fman]

This has been discussed before and there definitely is confusion on using fixed mounts. For some reason people feel like you will feel vibration in the car, steering wheel, foot box, etc...from my experience not the case. I have 4700 miles on my car now and have had zero issues with my 427 and fixed mounts. Not only do you gain hood clearance, the side pipes align better. The only downside is the engine sits lower so you must have a 7" deep pan on your engine or more than likely you will hang down below the frame.