1963 J-65 & 7 Leaf Spring??????????

[Duke W.]

Re: 1963 J-65 & 7 Leaf Spring??????????

"2. Due to the appearance similarities between metallic brakes and Z06's the operator installed the seven leaf spring in error?"

How could this be considered "probable" when, with the drum installed, it is impossible to distinguish between J-65 Metallic Brakes and base brakes? Didn't the trailing arm assemblies arrive at the axle/rear suspension subassembly area with drums installed? So the only way the operator could tell the difference between an assembly equipped for J-65 versus base brakes would be the assembly code on the trailing arm sub-assembly. Only the HD brakes looked obviously different due to the finned drum.

Installing the wrong part is a possiblity (Murphy's Law) but QA certainly would have caught it, and if they requested a deviation from engineering there is no way engineering should have approved it given the potentially dangerous handling characteristics the HD spring could create when combined with standard front suspension components, and this logic eliminates #1.

Duke

[Michael H.]

New 63 W/F40 Shocks

I know this certainly isn't proof but here's a brand new 63 with F40 and standard brake drums. This car is just over one week old. Thought this was interesting.

[Michael H.]

New 63 W/F40 Shocks *NM*

[Michael H.]

New 63 W/F40 Shocks

The first pic even shows the "unique to F40" shock pin. This one clearly shows the F40 shock with the large upper washer. Shocks certainly could have been changed by the new owner but I would never expect to see the lower pin changed to the F40 design. Could it be possible that there were a few factory F40 63's out there?

[Duke W.]

Re: New 63 W/F40 Shocks

A question: What is the source and date of these photos?

An observation: In 1963 tires were not yet big enough to warrant flares of that size, and modification of the wheelwells was illegal for production class racing anyway.

The Grand Sports did not receive the big flares to contain stock car racing tires until just before the December 1963 Nassau race. Grady Davis GS raced the entire '63 SCCA season with the production fender contours even though as a C-modified they could have done anything they wanted to make room for wider tires - HAD they been available

Duke

[Michael H.]

Re: New 63 W/F40 Shocks

"Custom Corvettes", May of 1963. Photos were taken in 2nd week of January and the car was just over one week old at that time. The finished product wore drag slicks and was driven on the streets of L.A. I have the owners name here somewhere. He sold the car almost exactly one year later.

I spoke with the owner over 30 years ago but never thought to ask about the HD susp. It certainly doesn't prove anything but it is interesting.

[Franz E.]

Re: Diff & Rear Drive On The Hook

Hi Michael: Do you know which model year that photograph was taken? I was in St Louis assembly in late 68 as the leaf spring supplier. Chevrolet's supplier of record was North American Rockwell's, Chatham facility. During that time frame the rear spring was being assembled to rear suspension module in the lower level, then transported to the main chassis assembly line. St Louis had a number of quality issues related to insufficient clamping loads on the spring plate resulting in premature spring failures. Assembly plants are living organisms and in a constant state of change. Over the years I was a direct supplier of suspensions components it was a constant battle. On a percentage bases there were more ECR's and deviation notices issues to St Louis than any other Chevrolet assembly plant.

[Michael H.]

Re: Diff & Rear Drive On The Hook

Hi Franz,

I can tell you for sure that it was 1981 or 82. I remember it was getting near the end of the St. Louis run and most likely within the last 6 months.

John Hinckley emailed earlier and told me that he remembers the spring being attached to the diff as it came up from the basement. He thought that method was used at least through the 60's. He also sent a pic of the 63 pilot line that clearly shows the spring attached to the complete rear susp/drive unit before it was installed on the frame. I'll try to dig through more pic's from earlier to see if we can nail down the point of change.

[Bill Jackson]

Re: New 63 W/F40 Shocks

Does the F40 shock pin have a number on it to identify it?

[Michael H.]

Re: New 63 W/F40 Shocks

Bill,

The F40/F41 shock pin should have a casting number 3829265-266 for L & R. The pin for standard suspension would have casting numbers 3820929-930. There was an extensive discussion about these arts in early January so if you check the archives, you will find pic's of both the standard and HD versions of this part. They are visibly different.