Early C1 Disc Brakes? SR1 or Sebring

[Tom W.]

Last week I posted info on this with a few replys that asked for pictures. These came with a set of Halibrand Sebring/Kidney Bean Magnesium wheels that I purchased. The 5.5"x15" wheels match these knock off hubs using a 5 on 4 3/4" pin spacing. As you can see, the snout is 2 1/2" and has 2 5/8" Halibrand spinner Nuts. The snout floats inside the clamshell design of the wheel hub housing and protrudes though openings on the front face.Tightening the spinner pulls the pins into the wheel drive holes. The rotor is cast iron and has a 3/8" thickness.
Anyone ever see these before and what may they have been used on?
John Fitch once told me they tried everything to get the 56 Vettes to stop at Sebring. I think discs were tried.

[Mike M.]

Re: Early C1 Disc Brakes? SR1 or Sebring

tom: your radiator needs cleaned. i have one of those brushes that will accomplish same. willing to trade brush for halibrands.mike

[Tom W.]

Re: Early C1 Disc Brakes? SR1 or Sebring

So much work...so little time. I'd rather polish the Halibrands.
Where are all the C1 gurus when you need them? Google indicated that Gib Hufstader ( Corvette Hall of Fame) worked on early brakes for Corvette. Do you know how to reach him?

[Mike M.]

Re: Early C1 Disc Brakes? SR1 or Sebring

tom: i'd check with dick robinson(philadelphia area) and john neas(tulsa area). mike

[Tom W.]

Re: Early C1 Disc Brakes? SR1 or Sebring

I'll get their contact info off the membership roster.
Thanks as always!
Happy Thanksgiving
Oh, here's one more pic for you. This is the label that was on the set of wheels.

[Bill M.]

Re: Early C1 Disc Brakes? SR1 or Sebring

That address is for Moon Equipment, where Shelby built the first Cobra. Google "CSX2002" and "Shelby"

[Stewart A.]

Re: Early C1 Disc Brakes? SR1 or Sebring

Wow ! Cool label but wouldn't they be for a Ford ? Stewy

[Tom W.]

Re: Early C1 Disc Brakes? SR1 or Sebring

I just spoke with John Fitch. He said the disc brakes didn't make it to Sebring in 1956. They finally got the drums working but he said the bigger problem was steel wheels. He said he couldn't count the number of wheel rims that separated from the center spider. He said that gave him "the thrill of his life". That's coming from a guy that raced Mercedes at LeMans, piloted a P51 Mustang and recorded the only confirmed German Jet fighter kill, and then parachuted out of his burning Mustang when shot down over Germany!
The only thing I can relate to his sensation is when your left front KO wheel surges past you after " a terrible wobble".
I also spoke with Bill Tower, owner of the SR2 Corvette. He has not come across the original disc brake plans for the first SR Corvettes but did work on the Grand Sport project and remembers those discs as the first actually used. C1 brakes could not have been disc in the final racing configuration due to FIA rules requiring 25 examples to be available to the public.
As far as the Shelby thing goes, right now the thinking is that the tires came through his shop (circa 1960) and were put on these Corvette configured Halibrands for SCCA or CSCC Racing. I'm going to try finding Paul Reinhart,Dick Guldstrand, Andy Porterfield, Doug Hooper, Jim Jeffords, and Bob Bondurant to see if any of those guys bought their tires through Shelby. Maybe those guys will remember a Chevrolet, or Halibrand project to improve Corvette brakes.
Anyone know where to contact these guys?

[Tyler T.]

Re: Early C1 Disc Brakes? SR1 or Sebring

John Neas has some GM documentation describing the testing of disc brakes in conjunction with the racing program.

Tyler

[Steven B.]

Re: Early C1 Disc Brakes? SR1 or Sebring

Tom, are there any stampings, etc. on any of the parts?

Also, many of the Halibrand equipped Corvettes (56-62) used tires of the 6.70 and 7.10/7.60 sizes. Early C-1's tended to use Firestone 170's and the later used GY Blue Streak. Your's may be tires added later to the wheels. Whatever the case, you have some great pieces of history.

Steve

[John N.]

Re: Early C1 Disc Brakes? SR1 or Sebring

I'll get their contact info off the membership roster.
Thanks as always!
Happy Thanksgiving
Oh, here's one more pic for you. This is the label that was on the set of wheels.

Tom
Would you print out what you think you read on that label?
Thanks

[John N.]

Re: Early C1 Disc Brakes? SR1 or Sebring

Last week I posted info on this with a few replys that asked for pictures. These came with a set of Halibrand Sebring/Kidney Bean Magnesium wheels that I purchased. The 5.5"x15" wheels match these knock off hubs using a 5 on 4 3/4" pin spacing. As you can see, the snout is 2 1/2" and has 2 5/8" Halibrand spinner Nuts. The snout floats inside the clamshell design of the wheel hub housing and protrudes though openings on the front face.Tightening the spinner pulls the pins into the wheel drive holes. The rotor is cast iron and has a 3/8" thickness.
Anyone ever see these before and what may they have been used on?
John Fitch once told me they tried everything to get the 56 Vettes to stop at Sebring. I think discs were tried.

Tom
By memory: The spinners shown do not match the flat 56 Halibrand spinners that I have seen. There were Halibrand spots tested at Sebring in approximately February by Duntov. He threw them under the bus. He maybe did not believe in disc at that time or the spots did not work well. I had a knowlegable person explain to me that the Halibrand spot would slow a lighter Indy car enought to make a turn at Indy but were not able to slow to a much lower speed a heavy Corvette at Sebring. John Hinkley has posted a Chevrolet proposed AIM or illustration page for the rear spots if they had been accepted. Maybe John can post it again. It would be neat if you have the spots that had been tested on the front at Sebring in 56. If you are close to Fitch maybe you could obtain pictures of the red 55 mule car that they used at Sebring in 56. If you would post those it would be a significant contribution to the hobby. IMO that is one of the most significant and unknown cars in the development of the performance Corvette.
Regards

[Tom W.]

Re: Early C1 Disc Brakes? SR1 or Sebring

The label says:
Goodyear Tire and Rubber Company
c/o Carroll Shelby
10820 South Norwalk Blvd
Santa Fe Springs, Calif.

Then there is a P.O. or order number underneath the address info.

The tire identification was just a bonus. The tires and wheels appear to be NOS. My interest was the wheel set. I' ve got a 56 and 57 Vette that I've decided to restore in period racing trim. So I always wanted a set of Halibrand K.O.'s for either and these came along.
Now that I've got the early Goodyears that have Shelby historical significance, and these weird Chevrolet type K.O. hubs with discs, I'm at a standstill because I don't want to start any restoration plans without giving this process the time to determine what the best application for all of this would be.
I've always been fascinated with Halibrands an also have two sets of Grand Sport wheels. I'm building a GS clone to put one of those sets on.
The racer cars and those that raced them are currently of interest because we don't have that many more years to gather their insights and event history.
Hope this info helps you to connect with other historical threads.
Tom

[Tom W.]

Re: Early C1 Disc Brakes? SR1 or Sebring

So far, I've not found any marks on them. I'm hoping the bolt heads will give me more info to share. As you can appreciate, just trying to determine how to clean away some oxidation without possibly destroying any faint markings is stressful enough. The guy I bought these from in Southern California had washed three of the four tires and destroyed the other Carroll Shelby labels. This one survived because it was the only one that had a sheet draped over it that caught years of shop grime. A custom painted hood was leaning against it and the owner didn't want the hood to get scratched. The Goodyear labels are still on the other tires because they were plastic film and survived the washing. That's how fragile luck can be.

[Tom W.]

Re: Early C1 Disc Brakes? SR1 or Sebring

I will talk to John and ask about that car. He's a great guy and always willing to contribute in any way.
He told me that his relationship with Duntov occaisionally had voids although they respected one another's capability. Zora would propose ideas and John would have the responsibility of sorting them out on the track. He told me in no uncertain terms that he let Zora know that the first Corvettes were simply "dangerous". Zora would diligently go back to work to find solutions but wouldn't always keep John abreast of those developments. Many times it was a mystery to John what Zora would bring to drive next. He was able to cope with it because there were some similarities to his days with Mercedes. You know...German engineers less than a decade after WWII. There were still lots of secrets in racing and the engineering guys didn't feel that it was their responsibility to answer to the drivers.
He told me he heard of the plans to try disc brakes since they were successful at Jaguar. But as you mentioned, the Corvettes were nearly a thousand pounds heavier. He personally never had a ride in any of the mules or Sebring cars fitted with disc brakes. I don't know who may have tested those. Maybe Duntov himself.
Tom