Need help with motor mounts
Thread Starter
Racer
Joined: Jul 2007
Posts: 339
Likes: 4
From: Northwest CT
Need help with motor mounts
I’m getting ready to install the engine back into my completed chassis and I need some help with motor mounts for a small block in my 78. When I removed the mounts, I didn’t notice that they were not the same on each side. One of the mounts measures 2-3/4” inside and fits snugly onto the frame horn. The other mount measures 3” inside (between two 1/8” spacers) and of course has about ¼” of “play” when mated to the frame. This mount also has oblong holes where the frame mounting bolt passes through it.
Is one of these correct and the other one wrong for this application? When I look up replacement mounts I see the same part numbers listed for right and left.
To complicate things, I have a mount from my 79 parts car and it is different from the other two. This one also measures 3” inside, but there is a ¼” spacer on one side only. It would seem to me that using this mount would change the driveline angle, no?
What is the correct thing to do here? Which one goes where?
Is one of these correct and the other one wrong for this application? When I look up replacement mounts I see the same part numbers listed for right and left.
To complicate things, I have a mount from my 79 parts car and it is different from the other two. This one also measures 3” inside, but there is a ¼” spacer on one side only. It would seem to me that using this mount would change the driveline angle, no?
What is the correct thing to do here? Which one goes where?
Le Mans Master
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
Both sides should be the same and fit the frame bracket. Buy new ones as they have a limited life span being made of rubber.Gary
Thread Starter
Racer
Joined: Jul 2007
Posts: 339
Likes: 4
From: Northwest CT
The problem with "just buying new ones" is that all of the listings that I see have photos that look like the "wrong" one that I already have. NAPA, Autozone, and the Corvette suppliers included. I can't believe that a mount that allows movement around the hardware is a good thing.
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
Autozone carries Energy Suspension polyurethane motor mounts. Chevys have tall/narrow mounts and short/wide mounts, they look very similar differing only by about 1/4". You can look up which is used on your car at the Energy Suspension website or at autozone for your application in rubber mounts. Go by the part number, not by looking at them.
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Racer
Joined: Dec 2009
Posts: 415
Likes: 10
From: Richmond Va
You can also measure the frame mount and see which one fits corrretly. Also, as stated before, there are short and tall versions. No ryhme or reason, per Chevrolet, but Novas, Camaros etc before 72(?), all used the same style mounts. I may be off the year by a little. After that, GM went to th clamshell version, due to the mount rubber breaking down and finally letting go.
Thread Starter
Racer
Joined: Jul 2007
Posts: 339
Likes: 4
From: Northwest CT
It seems that the Camaro boards have a lot of information on motor mounts. C3 small blocks use the same mounts as 67 - 68 302 & 350 Camaros.
I found the correct mounts in stock at Advance Auto. For future reference if anyone else needs these, they are Anchor part number 2285.
The mount on the left in my photo is the correct one.
Thanks guys!
I found the correct mounts in stock at Advance Auto. For future reference if anyone else needs these, they are Anchor part number 2285.
The mount on the left in my photo is the correct one.
Thanks guys!
