Shift_Happens

So what engine block date code should I be looking for to a 63 with a build date of Feb 2? I would assume a month or 2 before the car build date?

Nowhere Man

Typical is one to two weeks before cars build date. NCRS accepts up to six months. There was no first in first out rule either. If it was a common engine they didn't sit around too long. But if your engine combo is rare it's hard to say

Easy Rhino

Best would be January of 1963, but as Kieth said, you can go back as far as early August 1962.

It was recently pointed out to me that the small NCRS deduction for a non-matching block does not prevent earning top honors during judging.

My '65 came with a November '65 block out of a '66 Corvette, and the wrong serial number ("174"). It might as well have been a block out of an Impala.

The replacement block I'm building now was cast on 13 May (last hour of the second shift) and assembled on 14 May and my '65's final assembly date was 1 June 1965.

Note that the engine build assembly date can be after the body build date, but must be before the final assembly date by at least enough time for the engine to make it from the engine assembly plant of Flint, MI to St. Louis.

Also as Kieth said, there was no first-in first-out parts inventory control system in place, and the last engine in a shipment may have been the first one installed into a car out of that shipment.

NCRS allows the six months to account for the fact that some engine blocks may have gone to the back of the line for several reasons, including problems during engine assembly.

However, Nolan's book shows the engine build dates of numerous cars as compared to final car assembly dates, and while NCRS accepts up to a six month gap (because it has been evidenced in actual cars), the majority of engines were assembled within the month of the car final assembly date.

Shift_Happens

thank you both. Great info. I'm building a fresh motor for my 63 and I have the opportunity to purchase a December 62 block for my Feb build date car.
Just not sure I want to spend $2500 for a bare block

Easy Rhino

I agree.

FWIW, as you undoubtedly know by now, there are many available blocks for sale coming and going, and $2500 is on the top 1% of prices for a non-rare block. Hard to justify.

There are a handful of of bulk sellers that tend to run around $1200-1500, and have lots of dates available, even some closer to your build date.

It took me over two years to find mine dated about two weeks before my car's build date, and it is crack-free with original 4.000 bores, and even came with the rotating assembly (even though I'm not using most of that).

Of course shipping is expensive, and there is a lot of junk out there that you don't want to get stuck with.

Shift_Happens

Any bulk sellers you can refer me to?

Easy Rhino

PM'd you.