Dating the MGB GT engine and cylinder head

804

Most of the castings used for 1800 blocks and cylinder heads had date stamps as well that indicated when the casting was produced. This is slightly different from the engine code as the engine code appears to show the date of assemble.

With this information in mind I decided to try and figure out a little of the history for my 1967 GT. Let’s start with the original 18GB block.

In the grime under the oil filter canister there is a round date stamp as seen below. This is an easy one, the block was manufactured on January 4, 1967.

1967 MGB 1800 block date stamp
1967 MGB 1800 block date stamp

This is the engine plate removed from the block. 18GB U-H 67358

18GB is the engine type, U is for centre gear change, H is for high compression and 67358 is the serial number. Somewhere I have a list of when particular engine serial numbers were produced, I’ll have to locate this.

18GB MGB engine plate
18GB MGB engine plate

Next up is the cylinder head. The 67 GT used a 12H 1326 cylinder head. These heads have 1.5625″ inlet valves and 1.343″ exhausts and the rocker pedestal oil feed hole is in-line with the bolt holes. These heads appear to have been used from October 1964 to October 1967.This particular head was produced on November 11, 1966 as can be seen on the date stamp.

MGB 12H 1326 cylinder head date stamp
MGB 12H 1326 cylinder head date stamp
MGB 12H 1326 cylinder head
MGB 12H 1326 cylinder head

Both the engine block and the head are original to this MGB GT and the dates seem to confirm this. Here’s the MG VIN plate. Apparently the plastic BMC-67 plate was added when the car was imported to California. The car number GHD 3L 116543 means MG GT 3rd series Left Hand Drive with a serial number of 116543. This puts the car production in early 1967, I think I narrowed it down to March at some point.

That’s it for now. Next up I’ll look at the newer MGB 18V engine that I’m rebuilding.

1967 MGB GT VIN plate
1967 MGB GT VIN plate

1 COMMENT

LEAVE A REPLY

Please enter your comment!
Please enter your name here