Delco booster date decode

[My68SS]

Hi crew, the power brake booster in my 12C built 68 has 326 stamped into the front of the top lock tab, and 9078 stamped into the rear of the same tab.
Is the 326 a julian date - 326th day of the year? If so, how is the year determined?
Do the numbers look right for my car build date?
TIA

[baldeaglemtnman]

9078 is a 68 Camaro per Jonesy at Team Camaro.   http://www.camaros.net/forums/showthread.php?t=55781
Julian calender 001 = Jan. 1  365 = Dec. 31  1968 was a leap year so 326 would be Nov. 21 if I counted right.
Don't know the lead time on component parts but a month prior seems reasonable for your car.

[Jerry@CHP]

I would say it's the real deal.  This booster SHOULD NOT have the "Delco Morane" stamped on the front cover.  That should confirm it.  Over the years, many have sawpped out the front covers.

Jerry

[1968RSZ28]

Hi Rob -

   I just checked the power brake booster on my 02C Los Angeles built '68 Z/28.  It is also stamped 9078 on the back of the tab.  My julian date stamp on the front of this tab is 343.  When I count to 343 on a 1967 calendar I come up with December 9, 1967 which is a  Saturday!  

Jerry -
 
   Have you seen a Saturday date on these brake boosters before?

Paul  

[Jerry@CHP]

Yes, I have.  When I interviewed many of the Norwood plant workers who were transfered to Baltimore, I had asked them about that.  During that time period, I was told that there was no shortage of overtime for the plant workers.  Maybe John Z can jump in and tell us more?

Jerry

[My68SS]

I would say it's the real deal.  This booster SHOULD NOT have the "Delco Morane" stamped on the front cover.  That should confirm it.  Over the years, many have sawpped out the front covers.

Jerry

You are so on the money Jerry!      That is exactly the case, no 'delco moraine' stamp anywhere.
Your comment has precisely answered my next question regarding that stamping, as I know for almost certainty that this is the original booster to the car.

As for determining the year, is 9078 just a sequence number that is known to represent 1968?
What would the numbers be for 1967 and 1969?

Many thanks everyone for their input 

[1968RSZ28]

Yes, I have.  When I interviewed many of the Norwood plant workers who were transfered to Baltimore, I had asked them about that.  During that time period, I was told that there was no shortage of overtime for the plant workers.  Maybe John Z can jump in and tell us more?

Jerry

Jerry -

   Thanks again!  Once again, your expertise has cured my anxiety.  

Paul

[My68SS]

After some more thought, given my car was built late 67, the 9078 number must represent the 'model' year 1968 ?

[1968RSZ28]

Rob -

   I will quote from Jerry's book in an attempt to help:  "all 1967 and early 1968 Z/28 power brake boosters were stamped 8515.  Mid and late production 1968 Z/28 power brake boosters were stamped 9078."  I'd recommend both of his books even if you don't have a Z/28.  Here's the link:

http://www.z28camaro.com/index.html

Paul    

[My68SS]

Thanks Paul, I guess late Dec 67 has to qualify as 'mid' 68 model production, though it is only about 1/3 the way through the 68 model year.
Mine must have been amongst the first to get the 9078 number?

[Jerry@CHP]

1969's use a 9204, and there are two different size number characters that were used in 1969.  The early '69's use a large 1/4" stamp while the later boosters after Jan-Feb 1969 use a smaller 1/8" stamped number.

Jerry

[JohnZ]

The 9078 and 9204 are derivatives of the Delco-Moraine part number for the booster assembly, although the "tab number" isn't always the same as the last four digits of the Delco part number; the 3-digit number is a Julian date.

Saturday overtime was very common in the assembly plants as well as in the component supplier plants.

[My68SS]

Hi crew, my first post back here after a long......[long]absence. Talk about suffering withdrawal symptoms!!
Anyway, I have much to report on, but I won't unload here, I doubt that I would live long enough to tell all in any event!  I will filter relevant bits out as time goes by.
My baby finally has my undivided attention and I'm going over all her bits, documenting and taking pics as I go and first port of call are her brakes. IMO, effective deceleration is far more important than acceleration, in fact I have a rule of thumb, that a car should be equipped with such tyres, suspension and brakes that it can decelerate about twice as fast as it can accelerate.
Sorry to pick on this old dusty thread, but whilst searching booster specs and numbers, I found that I had started this thread on exactly this topic, so it gave me the answers I was looking for and I thought I would dust it off a little and add some pics of my stamps of the 326 numbers and 9078 numbers.
Cheers, best wishes to all, back with more soon 

[ko-lek-tor]

Good-day Rob,
A great welcome back! Looks like you are proficient in taking good pictures. Keep 'em coming.

[My68SS]

Hi James, thanks for the welcome back into the 1st gen fold and for your comment regarding pictures. Yes, I have been a keen photographer all my life including underwater photography when I was teaching scuba diving [USA PADI system] and also developing and printing my own black and white photo's at school [the school had it's own darkroom], so I will keep them rolling 
Just one question for now, I've noticed various rebuild kits for these boosters, just wondering if you or anyone has any recommendations - cost is irrelevant. Also if anyone knows of any tools or techniques to getting the two halves safely apart? I need to carefully open, photograph everything as I remove the bits and get the two shell halves gold dichromated again.
Cheers,
Rob