I know this subject has been covered in the past, and I don't mean to muddy the waters, but I for one was a little in the dark on this subject until recently, and just wanted to hopefully shed some light for others who may also not have all the info.

Firstly, the X308 engine number gives easy dating information. A typical number will be 010615 02:10. This indicates an engine build date of June 15th 2001 at 2:10

01=year
06=month
15=day
02=hour
10=minute

Secondly, there are two locations where the engine number was stamped, depending on the manufacture date. 1997 thru sometime in 1999 the engine number was stamped on the block casting next to the thermostat housing. Sometime during/after 1999 it was moved to a location on the block under the left-hand exhaust manifold.
The location under the left-hand exhaust manifold is easily visible if you remove the front left-hand wheel and look through the wheel well.
(For the longest time I didn't know there was an early, and a later location and I searched for the longest time in vain for the engine number on my 2001 VDP in the thermostat housing location!)

The third thing I read is the Nikasil bores were used up to and including engine number 000818 1042, engines after this used the steel cylinder liners. (000818 1043 on)

I hope this helps those who, like me, had been having a hard time finding their engine numbers

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Early engines had the engine number stamped in here, near the thermostat housing.


Here's a better picture of the engine number stamped on the block in the thermostat housing location. This particular one is 990603 0403, which translates to June 3rd 1999 at 4:03


The later production engines were stamped on the block just below the left-hand exhaust manifold, it is easily visible (may need a flashlight) if you remove the left front wheel and look through the wheel well.


A close up of my engine block, my engine number is 010201 02:41 which indicates February 1st 2001 at 2:42



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The location was not changed until 2001.

 

I wasn't sure exactly when the change took place, but I had read reports on this forum of owners with early 1999s having the number near the thermostat, and owners with late 1999 cars reporting the number being stamped near the exhaust manifold, but i have not had any personal experience, so can not be sure at all.


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