Author Topic: Big Block Distributor Hold Down Clamp  (Read 6262 times)

Camarocards

  • Member
  • ***
  • Posts: 118
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #15 on: July 18, 2013, 12:55:56 AM »
Thanks Ed.

My friends Vette is also a 427/390. Not sure of his build date though. I'll ask him what his build date is.

Thanks,

Bob
Bob
'68 SS L35 01D

Ed B

  • CRG Member
  • *****
  • Posts: 2333
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #16 on: July 18, 2013, 05:10:41 PM »
Here's an interesting tidbit. On the Corvette side of the world, it's known that the wire clamp was used on ALL engines in 1967. Since both Corvette and Camaro engines (as well as all the rest of the divisions) were assembled at Tonawanda and Flint, I can't see any 1967 engines using the stamped clamp.

Ed

Mike S

  • Hero Member
  • *****
  • Posts: 1272
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #17 on: July 18, 2013, 05:45:45 PM »
I'd be shocked if there are no other members here that have a BB 67 or 68 to reply to.
I'm not that lucky to have two 67 L35 BB's and both have the stamped clamp, especially on the survivor I have had since 1980.
I'll go play Lotto now  :)

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

Ed B

  • CRG Member
  • *****
  • Posts: 2333
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #18 on: July 18, 2013, 05:57:33 PM »
That's why this is such a mystery Mike. Your two engines should NOT have the stamped clamp and the 69 Corvette Bob referenced above SHOULD!! I can see this is going to be another one of those items that'll drive us all nuts!!

Ed

Camarocards

  • Member
  • ***
  • Posts: 118
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #19 on: July 18, 2013, 06:01:55 PM »
Ed - Well, here is more more interesting info. I found this picture in the '68 Chassis manual. Unfortunately, the picture is for a 6 cylinder engine but the interesting thing to note is that it clearly shows the wire type clamp.

Mike - What is the build date on your cars?

It's still a mystery to me why some cars have stamped clamps and others have wire clamps, particularly in light of what Ed reported in an earlier post. It also doesn't look like there is a rhyme or reason as to which size engine got which clamp since the Chassis manual shows a wire clamp on a 6 cylinder engine.

Ed B

  • CRG Member
  • *****
  • Posts: 2333
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #20 on: July 18, 2013, 06:22:34 PM »
Bob, 6 cylinder cars got the wire clamps from the beginning of time! Even way into the 70's. I don't think 6 bangers ever got a stamped clamp, but of course, in light of what we're seeing, who knows!

You can't go by images in the service manuals. Most of the time they just found a picture that was good enough to show what was being referenced. It may be from a prior (or even several years before) and may not even be a Chevrolet part! HERE'S another example of what I mean.

Ed

Camarocards

  • Member
  • ***
  • Posts: 118
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #21 on: July 18, 2013, 06:36:50 PM »
Thanks Ed. Looks like mystery continues!

67 RS Ragtop

  • Member
  • ***
  • Posts: 82
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #22 on: July 18, 2013, 06:46:07 PM »
My '67 10B LOS L-30 has the wire clamp. FWIW

68camaroz28

  • Hero Member
  • *****
  • Posts: 1119
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #23 on: July 18, 2013, 11:27:06 PM »
Our 12/21/67 built 302 had the wire holder where our 69 Nova 396 had the clamp. I as others have seen the wired clamp style on 68's.
Chick
68 Z/28 NOR 01B Orig motor/trans/rear
69 Z/28 NOR 07A Orig Block & GM Cross-ram/carbs
69 L34 Rest. Nova Father/Son Car
69 L78 Surv Nova Purch 4/69 31K miles
67 L89 Corv Tribute
68 Corv 427/400 Orig motor
07 Corv Z06
R 68Z build- http://www.camaros.net/forums/showthread.php?t=182584

Mike S

  • Hero Member
  • *****
  • Posts: 1272
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #24 on: July 19, 2013, 12:13:41 AM »
 The more accurate way to gauge this is when the motor was assembled being the distributor was installed then.
My 67 L35 block assembly date codes are:
T0214MZ and T0308MW - both have the stamped clamp.

Chick, I assume the 302 date is what is stamped on the pad?

This is certainly an interesting topic.
Mike

Camarocards

  • Member
  • ***
  • Posts: 118
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #25 on: July 19, 2013, 12:59:00 AM »
Well, I didn't think I'd cause such an in depth discussion when I posted my original question! I figured surely someone must have run into this during their restoration, I'd get my answer and continue on with my project. Boy was I wrong!!

Anyway, I thought I would start to tabulate what we know so far from all of the previous posts:

Year    Engine    Build Date     Clamp Type

67         L30          610B               Wire
67         L35          704B               Stamped
67         L35          705B               Stamped

68         Z28          801B              Wire
68         L78          806?               Wire
68         Z28          807C              Stamped
« Last Edit: July 19, 2013, 01:06:08 AM by Ed Bertrand »

Ed B

  • CRG Member
  • *****
  • Posts: 2333
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #26 on: July 19, 2013, 01:07:21 AM »
Bob, I put them in monthly order for you and added a year digit at the begining of each date code. i.e. , 610B would be the second week of October, 1966.

Let's keep it going folks.

Ed

Mike S

  • Hero Member
  • *****
  • Posts: 1272
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #27 on: July 19, 2013, 01:24:47 AM »
Hi Ed,
   Good compliation. As a suggestion, I think it would be more granular if the engine assembly date was recorded too being some units sat on the rack from days to months before being placed in the chassis. Maybe something like below?

Year    Engine    Engine Date   Body Date     Clamp Type

67         L30                          610B               Wire
67         L35         0214          704B               Stamped
67         L35         0308          705B               Stamped

68         Z28                          801B              Wire
68         L78                          806?               Wire
68         Z28                          807C              Stamped


Mike

Camarocards

  • Member
  • ***
  • Posts: 118
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #28 on: July 19, 2013, 01:46:23 AM »
Thanks Ed!

Mike - Good suggestion!

vtfb68

  • Member
  • ***
  • Posts: 406
    • View Profile
Re: Big Block Distributor Hold Down Clamp
« Reply #29 on: July 19, 2013, 03:30:07 AM »
Guys,

   68   L35    0321    805C    Stamped
     VT
05C LA RS/SS U2 712 L34 M21 BR
08E LA RS Y2 749 L30 M35
"In the pursuit of accuracy"