There are two different 1KZ cylinder head. We know them as 1KZTE and 1KZT. 

The Difference being:

1KZTE valve masking height = -0.010" below the head face surface

1KZT valve masking height = -0.040" below the head face surface

When ever replacing a cylinder head on a 1KZ engine it is highly recommended you check the valve masking height of the old head to remove any risk of fitting the wrong head. We do not have a clear date of when these heads switch over. Also due to the age of these vehicles there is a high possibility the original engine has been replaced. Meaning it could easily have either engine in it. 

Fitting an incorrect head to this engine will result in engine failure.

The simplest way to ensure you are fitting the correct head is to measure the masking height of the old head. We will not warrent the incorrect fitment of this head.