Julian date for master cylinder for 69 corvette

[Mark B.]

Can anyone provide info on what the julian date be on a 69 corvette that was ordered in 10/16/69 and built on 11/25/69

Thanks mark

[Jeff W.]

Re: Julian date for master cylinder for 69 corvette

11/25 is 329. I don't have my book handy so don't know what the convention was. Perhaps 9359 is the production date. But a 1969 made in November would have been built in November of 1968, right?

(Yes, I corrected my first post. I knew it was too early in the morning.)

[Don H.]

Re: Julian date for master cylinder for 69 corvette

Mark
November 25 julian date is 329.
Six months would be 180 days. If you subtract 180 from 329, i.e. 149, you would have the lowest julian number that would
fit within the 6 month time frame for NCRS dating of parts.

re. below-
Any master cylinder with a julian between 149 and 328 will conform with the NCRS date parameter for evaluating the date aspect of originality in the CDCIF matrix. In the real world, the MC originally installed on your car could have been dated anything but likely was dated 1-2 months before your car was built.

[Mark B.]

Re: Julian date for master cylinder for 69 corvette

Don, so i am to use 149?

[Patrick H.]

Re: Julian date for master cylinder for 69 corvette

Don, so i am to use 149?

Your car was built on Nov 25, 1969.

Pick a day in late October of 1969 that was NOT a Saturday or Sunday:

https://www.timeanddate.com/calendar/?year=1969

Oct 23 or 24 look good.

Find a 1969 Julian calendar:

http://chevellestuff.net/tools/jc_non_leap_year.htm

Go to the Julian calendar, and those are days 296 and 297.
So, you could use 9296 or 9297 and it would fit perfectly.

[Mark B.]

Re: Julian date for master cylinder for 69 corvette

Are they (3) or 4 digit number on the master?

Mark

Your car was built on Nov 25, 1969.

Pick a day in late October of 1969 that was NOT a Saturday or Sunday:

https://www.timeanddate.com/calendar/?year=1969

Oct 23 or 24 look good.

Find a 1969 Julian calendar:

http://chevellestuff.net/tools/jc_non_leap_year.htm

Go to the Julian calendar, and those are days 296 and 297.
So, you could use 9296 or 9297 and it would fit perfectly.

[Joe L.]

Re: Julian date for master cylinder for 69 corvette

Are they (3) or 4 digit number on the master?

Mark

Mark------


They were 4 digit codes. The first digit was the last digit of the year of manufacture. The 3 following digits were julian day of the year.

By the way, my original owner 1969 was built about September 14, 1969. My original master cylinder is dated "9253" (September 10). So, my master cylinder is dated just a few days before the car was built.

[Mark B.]

Re: Julian date for master cylinder for 69 corvette

Joe, I am so confused, I have people telling me numbers in the oct time frame. The order date of the car was 10/16/69 but car build date on the tag is 11/25. Are you located on LI?

[Don H.]

Re: Julian date for master cylinder for 69 corvette

Mark
It sounds as though you are ordering up a new (old) MC and you can specify the date embossed on it. I wish I knew how you can do that. Aren't you hoping to find an old used MC with some julian date that fits your cars build date? If so, you should try to find one made in the (9)270 to (9)325 julian number range, but anything from (9)150 to (9)328 fits NCRS parameters. Your original MC could have been dated just a few days before your car's 11/25 build date but just as likely could have been dated up to two months before. So, there is a range of julian numbers that will work for you. It should not be that confusing.

[Joe L.]

Re: Julian date for master cylinder for 69 corvette

Joe, I am so confused, I have people telling me numbers in the oct time frame. The order date of the car was 10/16/69 but car build date on the tag is 11/25. Are you located on LI?

Mark-----

The only way to know what the date was on the master cylinder originally installed in your car is to possess that master cylinder. I provided the date on a known-original master cylinder and the approximate date the car was built. However, that's absolutely not to say that all cars had this kind of date spread. As others have mentioned, as far as NCRS goes, it can be any date within 6 months prior to the car's build date. There is no "absolutely correct" date (unless you possess the master cylinder originally installed on the car).

I live a LONG way from Long Island----about 2,800 miles.

[Jeff W.]

Re: Julian date for master cylinder for 69 corvette

Can someone please address my confusion? Wouldn't GM be building 1970 model cars in November of 1969?

[Mark B.]

Re: Julian date for master cylinder for 69 corvette

I would kind of agree with you with that comment. I had pulled the tank sticker and it says 1969

[Terry M.]

Re: Julian date for master cylinder for 69 corvette

Can someone please address my confusion? Wouldn't GM be building 1970 model cars in November of 1969?

For everything EXCEPT Corvette & Camaro. 1969 Corvette production continued until December 18, 1969

[Mark B.]

Re: Julian date for master cylinder for 69 corvette

Thanks for the info Terry!!!

[Jeff W.]

Re: Julian date for master cylinder for 69 corvette

Interesting. So changeover of the line did not occur until after that. I wonder if that was simply to satisfy demand or some other reason.