Author Topic: 2 different rotors on my '68 Z28 - which is correct?  (Read 7604 times)

barsteel

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2 different rotors on my '68 Z28 - which is correct?
« on: November 03, 2015, 07:54:06 PM »
Hello -

As is typical, what started out as a "simple brake check to make sure the car is safe" turned into a "complete system overhaul with 100% factory correct date coded parts", or at least that's what I'm now shooting for.

Anyway, here's 2 pics of the rotors that came on my '68 Z28.  From what I understand, the 2 piece is the correct design.  Is that the case, or were both types used with different time frames, or ?.

The "hat" from the 1 piece is rubbing on the inside surface of the rotor, so my guess is that I should go with a 2 piece.

Any disadvantage to the 2 piece?

Thanks...

Chris

Mike S

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #1 on: November 03, 2015, 08:14:22 PM »
 To my knowledge the two piece design was used in 67-68 with four piston calipers  and the single piece in '69 when the calipers were changed from four to a single piston.

Mike
67 04B LOS SS/RS L35 Hardtop - Original w/UOIT
67 05B NOR SS/RS L35 Convertible - Restored

william

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #2 on: November 03, 2015, 08:25:53 PM »
Nope, '69s with J52 also used the two-piece rotor.
Learning more and more about less and less...

L78 steve

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #3 on: November 03, 2015, 08:26:25 PM »
The two piece was used in 69 also. My 04C has the 2 piece type.
69 Z/28 Dover White. SOLD
67 SS/RS Mt. Green 1W,2LGSR,3SL,4K,5BY,07C. SOLD
70 Nova L78 Blk. Cherry,Sandalwood,M21,02B

jdv69z

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #4 on: November 03, 2015, 08:44:35 PM »
Attached are pics of my 69 rotors which I believe to be original. Can still almost make out painted number on hub = 263J1?
Jimmy V.

KurtS

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #5 on: November 04, 2015, 03:13:07 PM »
The change to one-piece didn't happen until after 69.
Kurt S
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Petes L48

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #6 on: November 04, 2015, 04:02:20 PM »
Back in the 80s I had to use the newer one piece rotors, as I could not find the original 2 piece anywhere.  I had to have them turned down a little in that same spot where you show the caliper rubbing on yours.     

JKZ27

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #7 on: November 04, 2015, 04:47:58 PM »
When I did a factory style disc conversion on my 68, 7 years ago, the kit came with one-piece rotors with a groove cut for 4 piston calipers. I can't remember the vendor right away.

Has anyone used the reproduction rotors for/with the 2 piece hub?
John
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Boston14

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #8 on: November 04, 2015, 11:03:05 PM »
When I was rebuilding the brakes on my early 11D 1969 SS/RS convert., one of my rotors was under specs and was not able to be cut.  I could not find anyone making or selling just the rotor disc.  I bought a repro 2 piece rotor asm. from a vendor (Heartbeat City), but the hub had some differences from my original.  So I swapped the new rotor disc onto my hub (they matched up perfectly) and then trued the assembly on a brake lathe.  Now, using the original hub, my rotors match and are both at almost new thickness.  I put the new repro hub into stock as a backup in case I ever need it.
boston14

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Dover White with Black Top and D90 stripe, Red Standard Interior

z28z11

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #9 on: November 04, 2015, 11:52:28 PM »
I believe there is a difference between the '68 two piece and the '69 two piece rotors - at least they appear different on mine. I'll try to get pics or measurements to prove/disprove.

My 56,000 mile LS6 Chevelle (departed garage in 2011) had two piece rotors as well - still on the car presently as far as I am aware. Wish I had kept them -

Regards,
Steve
1968 Z28 M21/U17 BRG/W 1967 Chevy ll Nova SS 
1969 Z28 X77/M20/VE3 LeMans/W
1969 L78 X66/N66 Cortez/BVT
1969 Z11 L48/M35/C60/C06  1949 3100 5wd 235/6

Petes L48

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #10 on: November 05, 2015, 03:29:15 PM »
When I was rebuilding the brakes on my early 11D 1969 SS/RS convert., one of my rotors was under specs and was not able to be cut.  I could not find anyone making or selling just the rotor disc.  I bought a repro 2 piece rotor asm. from a vendor (Heartbeat City), but the hub had some differences from my original.  So I swapped the new rotor disc onto my hub (they matched up perfectly) and then trued the assembly on a brake lathe.  Now, using the original hub, my rotors match and are both at almost new thickness.  I put the new repro hub into stock as a backup in case I ever need it.

Thanks, I've been wondering about this and will probably do the same since I still have the good original hubs.  I wish someone would sell just the rotors.   

rare396bronze

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #11 on: November 07, 2015, 09:24:17 PM »
Camaro Central offers just rotor. Pretty cheap to.


KurtS

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #13 on: November 16, 2015, 02:15:40 AM »
What's the difference between 67-8 and 69 rotors?
Kurt S
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z28z11

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Re: 2 different rotors on my '68 Z28 - which is correct?
« Reply #14 on: November 18, 2015, 03:44:43 AM »
No discernable difference on mine - '68 Z as compared to the '69 Z 2 piece - look more identical than I remembered.

Regards,
Steve
1968 Z28 M21/U17 BRG/W 1967 Chevy ll Nova SS 
1969 Z28 X77/M20/VE3 LeMans/W
1969 L78 X66/N66 Cortez/BVT
1969 Z11 L48/M35/C60/C06  1949 3100 5wd 235/6