Under the valve cover where the valve springs are.
On the drivers side of the engine in back of the cylinder head there are casting numbers and next to the casting numbers are raised letters either 5.7 or 5.0.
The block casting numbers are on the top driver side of the bellhousing flange at the back of the engine. The engine code is stamped into a pad on the block deck in front of the passenger side cylinder head.
Drivers side, right in front of the cylinder head, there is a pad on the block, with a series of numbers, starting with 2 letters, usually.
Under the rocker cover.
chevy 350
casting numbers are on the back of the block. there are numbers on the pad by the head on passenger side front that will reveal information too
I don't believe 378999 is a valid casting number for a block or head, however, check the website,www.mortec.com, for SBC casting number information. For Chevy cylinder head specs, try this one: http://www.73-87.com/chevy_ids/sbheads.htm And, another good site for block suffix codes, block casting numbers, and cylinder head specs: http://www.chevy-camaro.com/chevy-camaro-engine-codes.asp Thanks, dave
A small or big block Chevy have a casting number on the top of the block behind the driver side head. MorTec has Chevy casting numbers listed online.
In looking over the casting numbers at mortec.com, I was unable to find anything that started with 1101 or ended in 3120. Also, none of them had more than 8 numbers. Perhaps it is not a Chevy number, or you may not have gotten the number correctly. On a Chevy v8 engine, there is a small flat surface in front of the passenger side cylinder head that contains numbers that can identify the engine and it's original application.
1969-1973 chevy 307
Remove the valve cover and you will see it stamped into the top of the head.
this page will give year and model type and application for all chev blocks: -MorTec, Inc. Chevy Smallblock V-8 Casting Numbers List- copy and drop this on your browser, then choose - -CHEVY V-8 BLOCK AND HEAD casting numbers-