Aluminum body mounts?
Thread Starter
Burning Brakes
Joined: Jan 2017
Posts: 1,096
Likes: 213
From: The Buckle of the Bible Belt. Joplin Mo
Aluminum body mounts?
Received my body mount kit yesterday for the 69. Guess I was surprised they are aluminum. Was thinking rubber was involved. Thought the corroded green chunks that came out were petrified rubber. I am sure members who have done this before find this post silly. Seems like I have seen newer C-3s with rubber bushings instead. Anyone know why GM used aluminum mounts on the older vettes.?
Race Director
Joined: Oct 2000
Posts: 12,683
Likes: 3,137
From: Shamong, NJ
68-72 Corvettes used the solid aluminum body mounts. When they went to radial tires in 73, the switched to the rubber mounts, to offset the harsher ride of the radials. Some owners have replaced their solid mounts, with the 73-82 rubber ones.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,482
From: Southbound
Cruise-In II Veteran
Le Mans Master
Joined: May 2006
Posts: 5,814
Likes: 414
From: Pittsburgh suburbs Pa.
Even though my 72 came from the factory with aluminum spacers I changed to the rubber but I will say that it requires a couple alterations because they are a little thicker and it changes the angle of the steering column where it meets the rag joint . You will have to lower the bottom end of the steering column to match the rag joint and that requires enlarging the fiberglass hole under the bottom of the steering column. Just a slight alteration and it doesn't change the looks of anything.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Solid spacers would reduce a bit of body roll when 'working' the car.
Rubber spacers would make the ride more pleasant. BUT, you would need to research the suppliers of those synthetic rubber parts to have confidence in their quality. Many vendors sell poor quality 'junk rubber' cushions, and you do NOT want them because they will disintegrate over time. Good quality rubbers will last another 40 years.
Choose wisely!
Rubber spacers would make the ride more pleasant. BUT, you would need to research the suppliers of those synthetic rubber parts to have confidence in their quality. Many vendors sell poor quality 'junk rubber' cushions, and you do NOT want them because they will disintegrate over time. Good quality rubbers will last another 40 years.
Choose wisely!
Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 780
From: Eustis ( Area 51 Bat Cave ) Fl
I had no clue radials ride harsher than bias plys...new tech for me there,
My 69 had at some point the aluminum mounts changed to rubber i knew that if i buy 73 up rubber mounts they are thicker i heard of special rubber mounts that are correct thickness for pre 73 but i couldnt find them i did find poly mounts the correct thickness for pre 73 and i used them...they will likely outlast me but in hindsite i wish i had ran aluminum mounts just because.
I would guess and just my guessing the factory went to rubber to help with noise and vibrations
My 69 had at some point the aluminum mounts changed to rubber i knew that if i buy 73 up rubber mounts they are thicker i heard of special rubber mounts that are correct thickness for pre 73 but i couldnt find them i did find poly mounts the correct thickness for pre 73 and i used them...they will likely outlast me but in hindsite i wish i had ran aluminum mounts just because.
I would guess and just my guessing the factory went to rubber to help with noise and vibrations
Thread Starter
Burning Brakes
Joined: Jan 2017
Posts: 1,096
Likes: 213
From: The Buckle of the Bible Belt. Joplin Mo
Thanks to all the heavy hitters who have posted on this topic. Although polyurethane bushings do sound like a good upgrade, thinking I will stick with the oem mounts. Nearly all the old Chevrolet's I have driven roll and lean in the corners, and they are all rubber mounted. Seems like a good reason to use aluminum. I am looking for the full on Corvette experience. Not going to be beating on this car when finished, but I will certainly be using it.
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,601
Likes: 7,048
From: New Or-leens Loo-z-anna
The local rubber products supply house made a set of spacers for me.....it took about an hour. They used conveyor belt material which has impregnated woven nylon cloth at 1/8" thickness intervals....Very Tough stuff.
No "offset-sqoosh".....no drastic compressing when torqued down...and I doubt any body movement.......$20 for the set...I added 1/8" thick stainless flat washers where needed to adjust door gaps, etc.
No "offset-sqoosh".....no drastic compressing when torqued down...and I doubt any body movement.......$20 for the set...I added 1/8" thick stainless flat washers where needed to adjust door gaps, etc.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
The local rubber products supply house made a set of spacers for me.....it took about an hour. They used conveyor belt material which has impregnated woven nylon cloth at 1/8" thickness intervals....Very Tough stuff.
No "offset-sqoosh".....no drastic compressing when torqued down...and I doubt any body movement.......$20 for the set...I added 1/8" thick stainless flat washers where needed to adjust door gaps, etc.
No "offset-sqoosh".....no drastic compressing when torqued down...and I doubt any body movement.......$20 for the set...I added 1/8" thick stainless flat washers where needed to adjust door gaps, etc.
Used repop rubbers on my abody could tell they wont be around long.
How hard is it to make decent rubber come on....
Team Owner
Joined: Sep 2006
Posts: 31,285
Likes: 4,375
From: Westminster Maryland
Hi,
"Nearly all the old Chevrolet's I have driven roll and lean in the corners, and they are all rubber mounted."
Wait a minute?????
The body mounts don't have anything to do with a car leaning and rolling in corners… that a suspension/tire issue.
The type of body mounts used is felt in the seat of your pants by your boney butt and kidneys when you drive over rough roads.
Regards,
Alan
"Nearly all the old Chevrolet's I have driven roll and lean in the corners, and they are all rubber mounted."
Wait a minute?????
The body mounts don't have anything to do with a car leaning and rolling in corners… that a suspension/tire issue.
The type of body mounts used is felt in the seat of your pants by your boney butt and kidneys when you drive over rough roads.
Regards,
Alan
Pro
Joined: Sep 2013
Posts: 657
Likes: 99
From: Slidell Louisiana
The local rubber products supply house made a set of spacers for me.....it took about an hour. They used conveyor belt material which has impregnated woven nylon cloth at 1/8" thickness intervals....Very Tough stuff.
No "offset-sqoosh".....no drastic compressing when torqued down...and I doubt any body movement.......$20 for the set...I added 1/8" thick stainless flat washers where needed to adjust door gaps, etc.
No "offset-sqoosh".....no drastic compressing when torqued down...and I doubt any body movement.......$20 for the set...I added 1/8" thick stainless flat washers where needed to adjust door gaps, etc.
Last edited by rajin cajin; Jan 29, 2017 at 02:16 PM.
Racer
Joined: Sep 2005
Posts: 359
Likes: 0
From: Shoemakersville Pa
Thanks to all the heavy hitters who have posted on this topic. Although polyurethane bushings do sound like a good upgrade, thinking I will stick with the oem mounts. Nearly all the old Chevrolet's I have driven roll and lean in the corners, and they are all rubber mounted. Seems like a good reason to use aluminum. I am looking for the full on Corvette experience. Not going to be beating on this car when finished, but I will certainly be using it.
Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 780
From: Eustis ( Area 51 Bat Cave ) Fl
Here's something to keep in the back of your mind. Don't know if your going with side pipes. When I rebuilt my 69 BB I chose the rubber instead of aluminum basically for the ride, but found out later on that because of the difference in height I didn't need to modify my rocker molding for the hooker side pipes. Win, Win