Prothane Motor Mounts

[palerider94]

Was planning on putting new Poly Protahne motor mounts in my car to go with the new 347. I've read some post that say that they will cause a lot more vibration. Both most posts are attributing it trans poly mounts. Anyone just running solid or prothane motor mounts with oem trans mount? Curious on vibration levels. thanks

 

[amorrow]

You will notice more vibration. I have poly Ron Morris mounts on my '65 with an OEM Toploader trans mount, and there certainly is more vibration, even with a camshaft milder than the one I had in the car when running stock engine mounts. That's not to say more vibration is a bad thing, though...it enhances the driving experience.

 

[tx65coupe]

I have the RMP adjustable mounts that are poly. There is a little more vibration, but its not that much I'm not bothered by it at all.

 

[66 Restomod]

I went with the TCP mounts, and they are great (and stock style trans mount for T5).

Good thinking to install upgraded mounts with a 347. The TCP and RMP mounts won't pull apart like the stock style. I think the Prothane are also stock-style, but with urethane instead of rubber.

If you are doing a T5 too and might need some adjustability, I'd consider the TCP or RMP as well. I noticed about the same vibration with the TCP as I had with a broken stock-style mount.

 

[rbohm]

what you can do to eliminate some of the added vibration, if you find it objectionable with poly mounts, is to use a poly mount on the left side, and a stock mount on the right side since the right side mount is under compression and doesnt fail like a left side mount does.

 

[DK832]

I put poly motor and tranny mounts in my 351/69 and had a lot more vibration at certain rpm. Had the driveshaft balanced = helped with 50% of the 'new' vibration. Put back the rubber tranny mount and almost went back to std level vibration exept for ~2000rpm where there is a harmonic. The main result from the poly motor mounts was that I removed a slight wheel hop when burning out.

 

[red302]

I used Prothane motor mounts in my '68 and have more vibration also. Mainly at about 2,000-2,500 rpm. It's not terrible, but you can definately feel it. Expecially if you are sitting at a stop and just rev the engine.