4 replies to this topic

[notna]

Hey all,

I know this would have been discussed before, and I tried to search for info, but couldn't sort the shit from fact.

Is there a table or database somewhere that lists vehicle model / month / year and corresponds it to V8 engine block casting number and engine prefix?

I'm after a 253 appropriate for my L32 SL/R. 8/76 build. Any well educated Torrie folk know what engine prefix and block casting number should be on that?

Cheers!

[yel327]

NR prefixed engine with any cast date.
It is pointless chasing yor tail with date codes and engine numbers. They are all over the place on high volume stuff like an SLR. Unless you have the original get an NR, and unless it is a concours resto i'd even just suggest any HR prefixed engine will do.

[notna]

Cheers for that.

The way I restore cars is by having everything "correct". It's just how I roll.... I'm a perfectionist and I have to know all the stupid little facts, like this.

I found the following on http://oldholden.com by letting my fingers do the googling. This helps me in one way, but also makes it damn hard now to find the right motor for my resto!!!!!

By Munromad 24/03/08@08:52 Casting dates are very simple to decode

The first on or two letters are the day of the month.

The letter is the month
A=Jan
B=Feb
C=Mar

I is not used so H=Aug then J=Sep

The last number is the year. 2=72, 3=72 etc

Earlier blocks (which have a different prefix on the engine number [253H]) will have the month before the day in the date code.

Later blocks such as 82, 83 etc can be distinguised from 72, 73 by having 4.2 cast on the side instead of 253.

There are also other differences as well but that is a very simple one.

When looking for a suitable block for a restoration try and find one that was cast somewhere between 1 and 4 months before the build date of the car as that is usually the way things worked out on the production line.

[yel327]

Problem is, there is only one "right" motor for your car and that is the original. Next best is an NR prefix. After that you might as well have a QR prefix. You can chase date codes all day long but it is really a fools errand as they can vary wildly (like by many months), depending upon when they are used (ie engine number stamped) and engine numbers can vary by many thousands between adjacent cars in the service/warranty records (same as the LC/J records off microfiche that are floating around) especially on lower volume engine numbers like a Torana 253. So at the end of the day you can find what you think looks "right" but it can and will be out by a lot from what the car had originally. Remember a car is only "matching numbers" once!
My advice would be to find an NR prefix engine, next best is any HR prefix. Trying to narrow it down any more than that will just give you a headache and no gain. A HR prefix one digit different to the original is no more correct that one 20,000 numbers away!

[notna]

Fair call.... points noted, and I agree that it will be a shit of a search for the right motor!