Where can I buy this??
Thread Starter
Drifting
Joined: Feb 2007
Posts: 1,498
Likes: 206
From: Pearland Texas
St. Jude Donor '09
Where can I buy this??
where and who carries these bolts ? I've looked at most of the common places and don't see them in their catalogs? also what exactly is their purpose of the long bolts with the spacer??
Drifting
Joined: Oct 2005
Posts: 1,615
Likes: 150
From: Forth Worth TX
Soak them in Evapo Rust http://www.evapo-rust.com/ Available at most auto part stores.
I soak fasteners (and all sorts of other rusty/corroded stuff) for 24 hours, have had great success.
I soak fasteners (and all sorts of other rusty/corroded stuff) for 24 hours, have had great success.
Last edited by Revi; Feb 3, 2015 at 07:40 AM.
Race Director
Joined: Oct 2000
Posts: 12,624
Likes: 3,097
From: Shamong, NJ
I don't believe that anyone makes new ones. They were only used on 74 Corvettes.
Those bolts are part of the 74 Corvette's attempt at energy absorbing bumpers.
Beginning in 1972, Federal law required that cars be able to sustain a minor impact, without causing damage to the car. Initially, I think it was a 2 1/2 mile an hour front impact, that was raised to 5 mph in 73. For 74, the rear bumpers were added to the law, and had to withstand a 2 1/2 mph impact.
Most cars met the requirement by just adding large cumbersome bumpers, front and rear. The Corvette's sales were partially driven by it's style, so GM had to come up with something better than the big metal bumpers, employed by most cars. Chevrolet's answer was a large metal bumper bar, covered by a urethane bumper cover, and mounted with the bolts and washers you have. Your front bumper should have similar bolts.
As I remember it, the bolt is larger than the washer. On impact, the bolt is forced through the washer. The resistance caused by the bolt's larger diameter, being forced through the smaller hole in the washer, absorbs the impact. The set up was basically a one use only solution, to energy absorbing bumpers, and was replaced by a shock absorber mounted bumper bar, in 1975.
I did have some of those bolts around, from a 74 we parted out years ago. I doubt that they're in any better condition, then the ones you have. I don't recall if they're fronts, rears or a full set. If I get a chance, I'll look for them later.
also what exactly is their purpose of the long bolts with the spacer??
Beginning in 1972, Federal law required that cars be able to sustain a minor impact, without causing damage to the car. Initially, I think it was a 2 1/2 mile an hour front impact, that was raised to 5 mph in 73. For 74, the rear bumpers were added to the law, and had to withstand a 2 1/2 mph impact.
Most cars met the requirement by just adding large cumbersome bumpers, front and rear. The Corvette's sales were partially driven by it's style, so GM had to come up with something better than the big metal bumpers, employed by most cars. Chevrolet's answer was a large metal bumper bar, covered by a urethane bumper cover, and mounted with the bolts and washers you have. Your front bumper should have similar bolts.
As I remember it, the bolt is larger than the washer. On impact, the bolt is forced through the washer. The resistance caused by the bolt's larger diameter, being forced through the smaller hole in the washer, absorbs the impact. The set up was basically a one use only solution, to energy absorbing bumpers, and was replaced by a shock absorber mounted bumper bar, in 1975.
I did have some of those bolts around, from a 74 we parted out years ago. I doubt that they're in any better condition, then the ones you have. I don't recall if they're fronts, rears or a full set. If I get a chance, I'll look for them later.
