How do you determine the Birth Date of 61 Vette

[Rod M.]

Can someone provide me with a way to determine the actural birthday of my car, so I can confirm the needed dates for the block, and heads.
Vin # 10867S104098

What date should the block be?
What dates should the heads be?

[Anthony S.]

Re: How do you determine the Birth Date of 61 Vette

Try the "birthday" calculator here: http://www.c1registry.com
It will give you an approximate date.

[Mike B.]

Re: How do you determine the Birth Date of 61 Vette

Rod,

It may run the same algorithm, but the NCRS Wisconsin chapter has a birthday calculator too: http://www.ncrswi.bizland.com/bday/bdaycalc.htm

I ran your serial number and it reported a December 23, 1960 birth date.

I believe for judging purposes, the engine block casting can be up to six months before car build date but in practice it is better to try to stay within three months. Also the assembly date (that stamped on the front pad) should be no more than one week before the car build date although there is plenty of evidence that suggests some engine/car dates were built within days while the castings were practically still warm.

The head dates must preceded the engine assembly date by a reasonable amount of time (few days to weeks before) to allow for the components to be matched during assembly. It would make no sense to have heads that have casting dates after the engine is assembled. Note that these dates are not checked during judging since they are under the valve covers so any correct (likely "powerpack") heads will be OK.

Your best bet is to buy an NCRS judging manual which is very helpful regarding dates and correctness if that is what you are aiming for. You can link to it from the main web page to this Forum.

Mike

[Mike B.]

Re: How do you determine the Birth Date of 61 Vette

Oops! Check that. I just re-read my reply.

"Also the assembly date (that stamped on the front pad) should be no more than one week before the car build date ..."

What I meant was no less than one week before the car build date. In other words, there is a necessary transit delay between when/where the engine was cast and when it was actually assembled before being installed in the car. According to the experts, anything tighter than a week is improbable but not impossible.

[Kenneth B.]

Re: How do you determine the Birth Date of 61 Vette

Oops! Check that. I just re-read my reply.

"Also the assembly date (that stamped on the front pad) should be no more than one week before the car build date ..."

What I meant was no less than one week before the car build date. In other words, there is a necessary transit delay between when/where the engine was cast and when it was actually assembled before being installed in the car. According to the experts, anything tighter than a week is improbable but not impossible.

It's only 10 hours by truck to ST Louis from Flint Mi. Sa long as it's a day or more it's OK.
KEN

[John H.]

Re: How do you determine the Birth Date of 61 Vette

It's only 10 hours by truck to ST Louis from Flint Mi. Sa long as it's a day or more it's OK.
KEN

A day is pretty tight - the engines were shipped by rail.

[Kenneth B.]

Re: How do you determine the Birth Date of 61 Vette

A day is pretty tight - the engines were shipped by rail.

John
I agree it's not likely but if there was a problem some where some engines could have been trucked. Awhile back Dana front difs. made in Fort Wayne In.,were trucked to Auburn and flown to Toledo Dodge plant because of a component problem at Dana.
KEN

[Rod M.]

Re: How do you determine the Birth Date of 61 Vette

Thanks for all the quick assistance. If the date of my car is Dec 23rd 1960, then the engine block I have (casting # 3756519) with date code L260 should be correct. I want to rebuild the engine to correct specifications and I don't have the correct year heads (casting # 3795896) based on the date (date code E154). Should I search for the correct year?

Any suggestion on how do a obtain the build sheet for this car? I want to find out if it had a dual carb set up or not. I would like to build the engine with 2x4 set up, but only if it does not effect me long term in points.

[John H.]

Re: How do you determine the Birth Date of 61 Vette

Thanks for all the quick assistance. If the date of my car is Dec 23rd 1960, then the engine block I have (casting # 3756519) with date code L260 should be correct. I want to rebuild the engine to correct specifications and I don't have the correct year heads (casting # 3795896) based on the date (date code E154). Should I search for the correct year?

Any suggestion on how do a obtain the build sheet for this car? I want to find out if it had a dual carb set up or not. I would like to build the engine with 2x4 set up, but only if it does not effect me long term in points.

Rod -

Your block was cast on December 26, 1960 (assuming it's a Flint block), so it's not going to work with a final assembly date for the car of December 23, 1960. If it's a Tonawanda block, L260 would be December 2, 1960, which would be date-correct, but Tonawanda blocks weren't used in Corvettes.

I don't have a '61 JG, but the Spec Guide calls for 3774692 heads (or 3782461 if it's a fuelie), not 3795896, which was used in '62 on 250hp engines.

There are no build sheets available from any source for pre-'77 Corvettes; you have to work from other "clues" to try and determine its original configuration.

[Rod M.]

Re: How do you determine the Birth Date of 61 Vette

How do I determine if this is a Flint or Tonawanda block. Either way I now will need to sell this block and find a correct dated one. I just purchased the car in Nov and they had this block with the car and told me it was the correct date code. Now I find out its not, so back to the drawing board. Where is a good place to sell or trade my block for the correct year? I will aslo sell the heads I have and intake too.

I wish I new all this before I purchased this car.

[Mike B.]

Re: How do you determine the Birth Date of 61 Vette

Rod,

If the car is running all right, why don't you enjoy it for a while before you go tearing things apart? Few people will know the difference and what you got in a vintage Corvette most could only dream about. My advice is to drive it, learn more about what you are after, then take the time to find the correct date and casting coded components so that you don't make any costly mistakes. Besides, the detective work is part of the fun of owning a vintage car!

To specifically answer your question, one of the quickest ways to discern between blocks cast in Flint and those in Tonawanda is that those from flint have a small, square-headed plug threaded into the top front of the block behind the water pump. Tonawanda blocks don't have this plug at all. Check out the attached photo for the relative location. I am not sure what, if anything, the plug was intended for, but that is the sure fire way to tell the origins apart, especially as in your case where the date code can be mistaken for part of the month. Otherwise, any cast engine component including blocks and heads, that have a two-digit date code are from Tonawanda (there probably are exceptions on some smaller bits and pieces). Flint components in contrast have a single-digit year.

In so far as where to find a good correct block check the archives of this Forum for recommendations or pick up a Hemmings magazine for several that advertise in there. Also check the Corvette Forum (search on line) they have a for sale/parts wanted section. You might get lucky.

If you have a Tonawanda block, I suggest that you strip out the good parts and use the block as ballast because that is about all they are good for on the resale market. A Flint block might be worth about $500 - $1000 depending on the general integrity and what's left of the original bore.

Happy Hunting.

Mike

[John H.]

Re: How do you determine the Birth Date of 61 Vette

Here's a close-up of the square-head 1/8" NPT plug found only on Flint blocks.

[Rod M.]

Re: How do you determine the Birth Date of 61 Vette

Not sure if you got this ohter thread

I was reading from the NCRS recommend books list. THE COMPLETE CORVETTE RESTORATION & TECHNICAL GUIDE - VOL.1 1953 - 1962 by Nolan Adams

Section IV Page 392

"The major parts of the corvette are dated, engine blocks, cylinder heads, intake manifolds and transmissions cases have part numbers and dates CAST into them.......Assembly dates are also stamped on data plates, on the generator, starter, distributor and radiator......."

Quote; "the date coding was alphabetical, the letter "I" being omitted because it to closely resembled a "1" - the resulting code as follows: A= January; B= February; C= March; D = April; F= May; G=July; H=August; J=September; K=October; L=November; M=December"

Here is a following 2nd example listed in the book below this entry;

....engine casting number K300 (October 30th 1960),.......Left Head date K180 (October 18th, 1960)......

There is no mention in the book as to manufacturing location of the block making the date any different?

It appears there is a casting date AND an Assembly date as some suggested.

In my example the CASTING date is L2 60 (it appears there is a little large space between the 2 and 6). So according to Nolan this a November 26th 1960 block?? or if its a Tonwanda date of Dec 2nd 1960.

I did find a number on the pad TI290D
T as in Tom
I as in Indian
290
D as in David

When I have the block machined and decked, and stamp with proper numbers what will identify this being a flint block or Tonwanda bloc?


I'm going mad

[Rod M.]

Re: How do you determine the Birth Date of 61 Vette

Correction TI209D

T as in Tom
I as in indian
209
D as in david

[Rod M.]

Re: How do you determine the Birth Date of 61 Vette

You mention there is a square-head 1/8" NPT plug found only on Flint blocks? I have this bolt in same location too.

Are we gettting closer? Thanks for all your help, its very intersting not sleeping at night, for not knowing what I have