CRG Discussion Forum

Camaro Research Group Discussion => Originality => Topic started by: 69Z28-RS on October 27, 2008, 06:54:56 PM

Title: 'late' '69 Z28 Valve Cover drippers
Post by: 69Z28-RS on October 27, 2008, 06:54:56 PM
Is there any evidence to show that 'late' (Sept and later 1969) Z28 valve covers had drippers?   I've owned my car since 1976; it has not been restored.   There was no evidence even when I purchased it that any work had ever been done to it, yet it had 'drippers' in the valve covers.  I'm hypothesizing that perhaps beginning at the time of 'normal '70 production' that the valve covers were updated to the drippers.   Current CRG information seems to claim that all '69 Z28 VC's did NOT have drippers?
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: firstgenaddict on October 27, 2008, 09:33:52 PM
makes sense because I have never heard that ANY 70 LT1 corvettes or Dueces had non-dripper covers...
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: 68Zproject on October 30, 2008, 02:10:22 AM
If you've taken them off you could check the part #s on the bottom.
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: Jerry@CHP on October 30, 2008, 01:22:42 PM
We have restored many sets of valve covers on late cars and they do not have drippers.

Jerry
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: jdv69z on October 30, 2008, 01:35:07 PM
When Chevrolet changed the design to include drippers, wouldn't the part no. stamped inside these change as well? I'm assuming the drippers would be included in the initial casting process?

Jimmy V.
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: firstgenaddict on October 30, 2008, 01:59:37 PM
Jerry,
Have you seen any non dripper LT1's or Dueces?
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: 69Z28-RS on October 30, 2008, 08:31:03 PM
When the design changed, the part number should have changed.  I have early Chevrolet Parts Manuals (69-72 dated) at home which I can check, but I  haven't yet done so.  I will check and see if there is a 'date' associated with the change.
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: 69Z28-RS on October 31, 2008, 05:10:44 AM
I checked the '69-70 Z28 valve covers I have. I checked 5 different covers; They were all the same; all had drippers and they had stamped inside the following pn's:     
P-3932417-LH  (this number was on only 3 of the covers I have)
P-3965543-LH   (this number was on all)
P-3965544-RH  (this number was on all)

There were also come other numbers stamped :    'C-1'     and   'CBC'   (these numbers were not on all of the covers).   There seemed to be 'two versions' of the PN's....

I also checked the September 1970 Chevrolet Parts Book I have.   For the '69 -70 SHP 302 and 350, the numbers provided were:     3965541-LH and 3965542 - RH.   

I'm curious if anyone has one of the 'non-dripper' VC they can check for the PN stamped inside?
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: Dave69x33 on November 10, 2008, 02:45:10 AM
Here is a picture of my non-dripper RH cover showing P/N-3932418.  This is off my 05A (May) 69Z.  I looked and I can not find my picture of the inside and part no. of my LH cover.

Years ago, I purchased a set of these covers from GM (service replacements) and they had the drippers.

Questions: What does the "A" stamping stand for?  Also, what does the "C-2" and "CBC" stand for?

Thanks,
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: JohnZ on November 10, 2008, 03:10:22 PM
Questions: What does the "A" stamping stand for?  Also, what does the "C-2" and "CBC" stand for?

Thanks,

Typicallly, "CBC" is the vendor identification, "C-2" would be a mold number, and the "A" in the circle would be an Engineering change level.
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: 69Z28-RS on November 10, 2008, 10:09:05 PM

Thanks Dave for the information on your RH cover.  It appears that the 'dripper valve covers' were an improved design, and replaced the original non dripper valve covers.  I'd love to find a date associated with the redesign.  I'm suspecting that your non dripper LH valve cover would have the 3932417 which is one of the PN's under the latercovers.   Does anyone have any data supporting the date of that change?

Thanks to John Z for his irreplaceable knowledge (and his sharing it) as always!   :)
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: Jerry@CHP on November 11, 2008, 02:14:41 AM
Have never seen any LT1 valve covers without drippers.  And we've restored hundreds of original sets.

Jerry
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: 69Z28-RS on November 20, 2008, 06:27:44 AM
Jerry,  I'm taking that you believe the last '69 Z28 (sometime in Nov '69) had non dripper VC's.. and the first '70 Z28 LT1 had dripper VC's?   IS that your belief?   Do you have any GM iinformation that supports such a date for that changeover?
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: Jerry@CHP on November 21, 2008, 01:48:07 AM
No info from GM but we have done original 11A Z28 covers and they did not have drippers.

Jerry
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: firstgenaddict on November 21, 2008, 02:24:45 AM
What is the earliest LT1 set you have done?
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: Jerry@CHP on November 21, 2008, 02:08:13 PM
We do not track the 1970 valve covers when they come in.  Plus, there's not as much activitly on 1970 valve cover restoration as there is on the 69 Z28s.

Jerry 
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: 69Z28-RS on January 08, 2009, 07:30:00 PM
In addition to the late production '69 Z28, I also have a late production '69 Corvette (with the 350hp/350 ci engine.   This car is a 41,000 mile orignal car which I've owned for over 20 yrs, having bought it from the original ower (a lady I worked with at the time).  I had occasion to remove the valvecovers last night, and found that this car also had the 'dripper valve covers'   This car was produced in August of '69, with the engine being assembled on 072569, very similar time-wise to the production of my '69 Z28 (owned for 33 yrs and which was also owned by a lady driver previously).   With both of these cars having 'dripper' type valve covers, I'm thinking either 1)  GM began putting on the dripper valve covers prior to the end of production in late '69, OR 2) these lady drivers couldn't stand having 'dripper less' valve covers on their engines, knowing that the '70 models had 'drippers', so they both purchased replacement valve covers??   (Both of these cars were in extremely original condition even when I purchased them in the 70's and 80's respectively..  I just wish there was some way we could pin down in a documented fashion, exactly when GM began using the dripper VC's..)
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: luv2sixty9 on August 06, 2011, 07:16:53 PM
I have a late 11A Z28 that came factory equipped with the drippers.
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: canadair on August 08, 2011, 06:37:47 PM
this is to luv2sixty9 if the valve covers did have drippers which I believe they did what was the size of the notches cutout for the intake runners where all 4 notches 3'' like the 418 valve covers or the latter with 3.5'' and 5'' cutout.
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: lynnbilodeau on September 25, 2012, 05:45:00 PM
I realize this is an old thread.  I also believe some of the late cars could have drippers.  I just bought an all original 350 horse 350 HW code engine assembled for a Corvette in late October (lots of guys don't realize the Camaro wasn't the only extended production in 1969; they did Corvettes all the way into December!).
This engine is standard all the way, and the original valve covers have drippers.  I will have to look at the part numbers, but will post this weekend.

Lynn
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: keech on September 25, 2012, 06:52:44 PM
mines an 11A car.     no drippers.     Jerry restored them for me.  beautiful job.
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: 69Z28-RS on September 25, 2012, 08:08:33 PM
a lot of people *restoring* '69 Z28s hunt for and find 'non dripper' VC's because that is what they are told was 'original'...    I'm fairly certain in my own mind that lots of 'late production 1969  350 hp Corvettes and Z28's got dripper type VC's in the factory.   I've had many people with late cars write me and tell me their cars also had dripper VC's, but they had believed they'd been changed (due to the 'common information' that '69's didn't have drippers and '70's did have drippers.    Based on the evidence from many inputs, it is also possible that there was not a 'changeover' date when they switched, but instead at some point in mid-summer '69, the VC was redesigned for the drippers (an improvement but without any other impact or appearance change), and when the new production came in, they began being used (mixed with any leftover dripper-less covers).   There's no reason Chevrolet would have declared ''69's do not get drippers and '70's do get drippers!   The VC design was updated and the parts were used when they came in...
Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: enio45 on September 30, 2012, 07:01:57 PM
Further to the late cars with the dripper valve covers....my car is a late 69 build, 10D. I'm the second owner and the orig owner swore up and down those were the orig valve covers that came with the car - HOWEVER, my valve covers are shinny, not the dull finish as seen on other 69Z's.  Any thoughts on the finish?? 

What was the finish on the 70Z28 camaro's?   

Title: Re: 'late' '69 Z28 Valve Cover drippers
Post by: lynnbilodeau on September 30, 2012, 11:19:14 PM
I have identified at least 4 different versions of these valve covers in aluminum, not including the black wrinkle finish ones.

The earliest without drippers are the 418.  They were used in 69 only.  I believe the second design, with drippers, but same exact appearance, appeared late 69.  Both were dull finish.  Part numbers on the first ones with drippers ends in 417 instead of 418.

They are exactly the same on the outside, including the reliefs cut on the inside edges to clear alumiinum manifolds.  Those reliefs are each 3 inches long.  The next set has a part number ending in 208 and 207 for rih and lh.  They are the most common and I believe most were polished originally.  Easiest way to id them on a car is the reliefs.  One is 3.5 inches and the other is obviously longer at about 5 inches.  The reliefs on the early ones are sometimes a bit crude, and appear to have been cut by hand.  The later ones are always perfect.

Adding the the confusion is the number of early valve covers, both with and without drippers, that were sanded and polished.  Eddie, you may have a set that someone polished.  If they have the short reliefs and end in part number 417, I think there is a very good chance that they are the originals.   I just took a set off a very original 350 horse 350 assembled 10 18 69.  This engine is so original the main and rod bearings are dated 9 of 69!  Never been apart.


Tried to add pics and more text but it deleted because it is too big.  Will send you pics via email.