Re: Early C1 Disc Brakes? SR1 or Sebring
CERV 1 originally had kidney beans. Any possible relationship there???
CERV 1 originally had kidney beans. Any possible relationship there???
-
-
Re: Early C1 Disc Brakes? SR1 or Sebring
I'm sure it's possible. If you look at every significant GM Corvette design prototype, and racing development vehicle, nearly all were on Halibrand wheels. The tires also make the connection more interesting. Not just the "Shelby" thing, but the size. The fronts are 6.00/6.40x15, and the rears are 6.50/6.70x15. This effectively would lower the car as well as allowing gear sets that enhanced top speed increases on long straight sections of track. The solid one piece casting and weight savings were also very forward thinking at that time. Chevrolet waited for a decade before they finally introduced cast wheels. It wasn't even Corvette...it was the 1975 Cosworth Vega.Comment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
Tom -
The Cosworth-Vega wheels were made by GKN (England), and I destroyed the first two prototype wheels ($5,000 each) they supplied to Engineering in mounting trials in my 550-per-hour wheel mounting system at Lordstown; that's a great story for another time.
Comment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
Thanks for that information, I got slightly ahead of myself and left out the words "spin cast" on that thread. I guess Halibrand, Kelsey Hayes, GKN, were all suppliers to GM but I'm not sure if Halibrand ever supplied anything for production.
One of the folks that replied to this inquiry said you may have an AIM from 56 showing the Halibrand rear sport discs that were to be tried at Sebring. If you could email it to me, thay would be interesting reading.
Thanks for your comment and help.
I've got to hear the Vega wheel tradgedy story when you have time.
TomComment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
Tom -
I posted a photo of the A.I.M. sheet above, but the upload robot reduced its resolution; I need your e-mail address to send it to you, and I'll include the article I wrote for the Cosworth-Vega Owners' Association newsletter on the wheel mounting disaster. Can't attach files to the internal board e-mail system.Comment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
Tom
Cast magnesium Halibrand KO wheels were used on the St Louis 1956 production SR Corvettes.
RegardsComment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
Hi John,
Short of the "Support" and "Brake Cylinder", the rest of what I have appears to be as drawn in the AIM you provided. My email to send a clearer version to is: luvfilters@aol.com
I also have 1975 Cosworth Vega 1675. The car came with a complete set of blueprints from the Lordstown Plant that feature Bendix Fuel Injection. I don't have them in front of me at the moment but there are a number of names and shift notations on the jacket that contains the blueprints. I'm sure it would be of interest to you.
Thanks again,
TomComment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
This reply appears to have gone to John Neas.
Hi John,
Short of the "Support" and "Brake Cylinder", the rest of what I have appears to be as drawn in the AIM you provided. My email to send a clearer version to is: luvfilters@aol.com
I also have 1975 Cosworth Vega 1675. The car came with a complete set of blueprints from the Lordstown Plant that feature Bendix Fuel Injection. I don't have them in front of me at the moment but there are a number of names and shift notations on the jacket that contains the blueprints. I'm sure it would be of interest to you.
Thanks again,
Tom
I had two "johns" reply to me on this thread so hopefully both will get this message.
I'm beginning to believe I just might have Corvette's first attempt at disc brakes!
TomComment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
Tom
The bearing sizes and length of spindle was different on the SR Corvettes. I do not know if this was true on the disc brake attempt.
RegardsComment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
Hi John,
I tried a search of the part numbers on the 2-15-56 AIM but wasn't able to find anything yet. I pulled out an old steering knuckle and decided to try the disc with it. The inner bearing looks very close. The outer bearing requires that I separate the two halves of the housing to gain the access I need. Once I get the drum brake backing plate removed, and I have a stripped knuckle to work with, I'll be able to tell more about compatibility.
If what I read is accurate, there were only six SR Corvettes produced in 1956. To date, only two are accounted for. Do you know why they used the drum brakes when the AIM shows this disc configuration? Or is it possible, some of the SR cars that cannot be accounted for may have had this disc brakes?
Thanks,
TomComment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
G.M. was trying to be as FIA legal as possible. They probably prepared the AIM to be ready if they used the disc. I have a portion of the parts list and Sebring was a work in motion. John Fitch talked about it in his 1959 book. I dont believe the disc were on any St Louis production SR cars. The final parts list has no evidence of disc. What was the linage of your parts? That might tell more of the story.
RegardsComment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
I'm trying to determine that linage now. I wrote to Carroll Shelby today to determine if these were parts sent to him to experiment with. As you know, before Shelby embarked on the Cobra and Shelby America, he was one of America's most prolific drivers. Since he was asked to drive the Sebring cars in 56, he had some relationship with GM. There was always activity within the domestic racing community.Particularly when racing success meant sales success. Duntov and Shelby would have been a natural partnership.
There was some mention that the estate that these came from was a guy that worked in engineering for Vic Edlebrock. I'm following up on that lead now.
Was my information correct that there are only two of six SR's known to exist today?Comment
-
Re: Early C1 Disc Brakes? SR1 or Sebring
The January 29/30, 1956 brake test at Sebring was an evaluation of DRUM brakes, not discs.
A larger finned drum was used with Marshall-Eclipse Ceramettalic linings.
Upshot of the tests seems to be to increase the width of the front linings from 1 7/8" (as tested) to 2 1/2".Comment
Comment