63-64 Judging Guide Question

[Michael H.]

Have a question about an item in the 3rd edition of the 63-64 Judging Guide. On page 139, item 25, front suspension, it states that;

"IN 63-64, THE Z06/J56 (SPECIAL PERFORMANCE/HEAVY DUTY BRAKE EQUIPMENT) USE FINNED BRAKE DRUMS WITH OR WITHOUT VENTED BACKING PLATES, FANS, OR AIR SCOOPS, DEPENDING ON THE OPTION"

I am not aware of an option that includes just the finned drums but does not include the backing plates, fans and scoops. Possible I suppose but what would the option number have been? Does this same info appear in the 4th edition of the JG?

[Dennis C.]

Michael, Have no TIM&JG at my fingertips...

...but my miniscule understanding is that the J56 offerings of that era pretty much only included metallic brake linings only, using the standard backing plates and drums. Maybe different shoe return springs...??? The ZO6 type drums are not 11" as I'm sure you know, so there is little possibility of combining the two options. Hope I don't get my hand slapped for this HO...

[Duke W.]

Re: Michael, Have no TIM&JG at my fingertips...

Dennis - I think you have confused J-56 with J-65. The JG does it too. J-65 was the "Metallic Brakes" option. It included sintered (segmented) metallic linings and return springs designed for greater operating temperatures. The drums had a finer surface finish and the front drums ('63-'64) have thicker webs, but are otherwise indistinguishable from base brake drums.

In the C1 era the option number was RPO 686, and 686/J-65 was quite a bargain at about 40 bucks during the drum brake era. Though limp when cold, and sensitive and touchy when hot they hauled my SWC down from significant triple digit speeds back in the days of yore, and, without them, I probaby wouldn't be here to talk about them, today. One had to learn good brake modulation skills to use them effectively under all conditions.

The '64 J-56 brake package was the option number for the HD brake system that was unbundled from the '63 Z-06 option.

J-56 disappeared in '65, but came back in '66 as the HD disk brake system.

Duke

[Duke W.]

Uh-oh...

...is this going to be another thread about the '64-'64 JG?

The manual is clearly confused and can't differentiate J-65 from J-56. It needs rehabilitation, perhaps a 12-step program...

Duke

[Michael H.]

Re: Michael, Have no TIM&JG at my fingertips...

Duke,

I may have confused the issue slightly by not including the info for J65 met brakes. Here's the entire part of the paragraph that pertains to Z06, J56 and J65.

BRAKE ASSEMBLIES

"In 1963, the Z06 (special performance option) use finned brake drums with or WITHOUT vented backing plates, fans or air scoops, depending on the option. In 1964, J56 (heavy duty brake equipment) use finned brake drums with or WITHOUT vented backing plates, fans or air scoops depending on the option. The J65 (sintered metallic brakes) use a drum with a special internal finish; However, the outward judgeable apperance is the same as the standard drum".

[Kenneth S.]

Re: Michael, Have no TIM&JG at my fingertips...

To answer your original question, the Fourth Edition says exactly the same thing.
Ken

[Michael H.]

Ok, Lets Try This a different Way....

Would it be more accurate if the words "OR WITHOUT" were deleted in two places in the original text? Does anyone disagree that there was no such option that included finned drums but did not include vented backing plates, fans and air scoops?

All 63 Z06 and 64 J56 options included the finned drums, vented backing plates, fans and air scoops with segmented metallic brake shoe lining.

Please let us know if you disagree with this or you have any documentation that shows such an option exists.

[Eric J.]

Re: Ok, Lets Try This a different Way....

Were the vents covered at the time of delivery with ears in trunk errrr.... cargo are like RPO 687/4 solid axles? Eric

[Michael H.]

Re: Ok, Lets Try This a different Way....

Eric,

Yes, the backing plates had covers installed over the screened area and the air scoops were shipped in the car. There was also a small bag that contained bolts to attach the scoops that was shipped in the IP compartment.

Not sure but I suspect the C1 RPO cars also had fasteners for the scoops that were shipped in the car?

[Verne Frantz]

Re: Ok, Lets Try This a different Way....

Michael,
This is the first mention I've read about the "covers" over the screened areas. The covers were die stamped metal plates. They also came on the '63 RPO Z-11 Impalas. There is no record that I know of pertaining to air scoops or fasteners shipped with the Z-11 cars. (They only needed to brake hard ONCE per drive.)

Verne

[Mike M.]

Re: Ok, Lets Try This a different Way....

mike: i've always been under the impression that the new owner simply removed the plates and used the same bolts to attach the elephant ears to the backing plates.no one has ever removed the covers from my Zo6 and the scoops were laying on the 36 gal tank cover when i first saw the 63 in 1969.regards, mike

[Michael H.]

Re: Ok, Lets Try This a different Way....

Mike,

Can't remember exactly how this goes but there were at least two screws shipped with the car that were to be used for scoop attachment. I think some of the cover attaching screws were reused for the scoops but there were at least two locations that required a longer screw assy. I have a few here somewhere. I'll dig out the info.

[Michael H.]

Re: Ok, Lets Try This a different Way....

Verne,

Pretty sure the air scoops were Corvette only. Not sure about this but I believe thr Z11 pass cars used only the vented backing plates but I don't think they used the finned drums and fans. The brake lining was unique to Corvette, different than Z11. I think Z11 had it's own lining.

[Robert Jorjorian]

Re: Ok, Lets Try This a different Way....

Michael I beleive you reuse one (1) of the existing cover bolts
then use two (2) longer bolts that are provided in a bag for scoop installation.

[Michael H.]

Re: Ok, Lets Try This a different Way....

Ok, thanks Robert. That's what I thought. I knew there were a few areas of the scoop that were much thicker than the cover plate so those locations would require a longer bolt.