in one of my camaros. there is a 427 425hp motor im trying to find out
what it is. here are some of the #. the casting # is (3369512) the # on
the pass front is (to 122 Ls) there is other #s on the block on the dr.side
rear it says gm and underneath that it says (con v2) and above the gm
mark it says (4 b59) i dont know the second # or letter i couldnt read it.
and i have not looked at the date code yet. dos anyone know what it is?
thank you

It's a 1969 427/425 Special High Performance with a Turbo 400 from a Full Size car. The block is probably 3963512 and the T0122LS indicates it was assembled on January 22nd, 1969. The casting date isn't right though. Recheck that number. Should be A xx 9. Rereading your numbers, Maybe it's A 05 9??

Ed

yes the casting # is(3963512) ill look at the date code agian tom. what dos the ls mean? and how do you know it came out of a pass. car?
thanks for all of your help.

Jeremy,

The "LS" is the indicator of what it was originally installed in. You can also check for the VIN located either on the passengers side of the block (in the same area where you found the T0122LS), or stamped on the boss by the oil filter. (The later is VERY difficult to make out sometimes.)

Ed

The numbers are RPO codes (RPO stands for Regular Production Order) developed by the factory for internal use (we can think of it as inventory control if you'd like). Because there is a great deal of interest in all things automotive and Chevy in particular people learned what the codes meant and then wrote books on the subject which over time have grown to include everything that GM ever did with the car (even though GM itself threw away most of the existing paperwork it has been preserved by enthusiasts).

Because of this we can tell when a part was cast (date code), machined (casting number identifies the blueprint to which it was machined) and assembled. In what factory it was built in, (build code) and the specifications published originally as to what rating was on the finished engine (the engine code) and where it was destined to be installed.

With the block numbers we also have a partial (vehicle specific) VIN of the car which can be traced back to a dealer, and through public vehicle registrations to whom it was originally sold (and then resold on down the line to the present owner (Scary huh)).

These numbers determine if your vehicle is numbers matching (all the numbers have to agree with what is known about the assembly process, and match the car it appears in by VIN) or not. Since your engine was destined for an Impala SS it wouldn't qualify as numbers matching car with some people. I personally think it's great that both car and motor have survived. A 425 horse 427 BBC is a fantastic motor to find in any Camaro, regardless of were the paperwork says it belongs.


Larger Dave