I have done a "motor mount" search on the c-5 tech forum and read 5 pages of posts trying to fine the size of the motor mount.

I went to the internet auction site to fine a picture of a motor mount and found two things. One, the solid and urethane items shown, differ greatly in appearance with the picture of the stock item,

The stock mounts look rather low and wide, where the aftermarket models are tall and thin. Now it is hard to tell from the pictures
but I would say the aftermarket item is about one inch taller than stock. Can someone givbe me the exact dimensions (of the rubber) on the stock unit?

 

My poly mounts from that internet auction site were the same height as the factory mounts, I've been very happy with them.

 

Great, exactly how tall are they (exlcuding the bolts).

 

~2-7/8"

(I have 2 sitting on the shelf, had one bust, they had a bad batch of polyurethane apparently. Called up and had a new set, with harder polyurethane, sent out to me at no cost no questions asked)

 

Ok, now we are talking.
Let me explain. I need motor mounts on my c5. I have been thinking of several options.
By way of background. Several years ago I wanted to put solid motor mounts on my 427Cobra replica. I had a machine shop
turn down some bar stock and make what looked like aluminum hockey pucks. Shortly after I installed the aluminum
mounts I noticed some unwanted vibrations and since I was taking the car off the track removed the aluminum mounts.

But I always described the solid mounts as aluminum hockey pucks. So I got to thinking when I replace my C5 motor mounts
I will use a stack of hockey pucks with a hole drilled down the center and a grade 8 bolt. A hockey puck is one inch tall and made of very
hard rubber. I am thinking it will be harder than stock but softer than poly or aluminum. Now if the hockey pucks don't work and the only
thing I think will be a problem is their reaction to heat, I could easily remove the bolts from the bottom and slide out the pucks and
slide in a cylinder of urethane.

So that is why I wanted to know the dimensions, "three hockey pucks high".

Thanks,.

Jay B

 

Take it from someone that has been doing this for a long time both as a hobby and professionally.....hockey pucks are the worst motor mounts ever.

Hockey pucks are much stiffer than the polyurethane used in motor mounts, do not hold up to heat or oil well, and split after a while. In addition, you will be running a solid bolt through coupling the subframe to the engine directly which is not at all how any decent motor mount works. In a poly motor mount, the attachment points are isolated from one another by the polyurethane and are not tied together by a stud all the way through. This makes a huge difference in vibration. The hockey pucks are so stiff they do not end up absorbing hardly any of the vibrations, so you end up with something about as harsh as solid motor mounts but much less reliable.

Go stock, go solid, or go poly....don't waste your time on hockey pucks.

 

I would just spend the extra $$$ and buy the pfadt motor mounts
http://www.pfadtracing.com/catalog/p...products_id/99

I thought I remember reading somewhere that using these makes the whole car shake with revving the engine?

 

Since my ideas are not based on experience but just theory, I welcome your thoughts.

I am now leaning to going with stock. My car is not a daily driver used mostly as a HPDE car. HP is only 366 RWHP but since I did trash one mount at the drag strip I was concerned that stock would not hold up. Then again
the stocks mounts were 90,000 miles old.

Thanks for the great advice.

Jay B