Cylinder heads
The cylinder heads are unique from left to right due to a spot for the distributor, although you can convert the heads by changing the caps and line boring the cylinder head. The early cylinder heads (’88 through ’90) had a smaller pilot hole for the distributor than the later ones which were 10mm.

To make a universal application, some shops have successfully machined the pilot holes to 10mm to fit later applications. This can be done without any problems if used on an earlier application with the smaller piloted distributor. The left and right camshafts did not change throughout the life span of the motor.

Timing components
The belt tensioner used from ’88-’92 was a spring loaded tensioner (Toyota p/n 13505-65020). In 1993 the tensioner went to a hydraulic style (Toyota p/n 13505-65040) (see photo on page 38). To accommodate this change, the front of the right-hand cylinder head has a machined recess and a drilled and tapped hole. Earlier heads may be machined to be adapted if necessary.

The timing belt was also changed to accommodate the difference in the tensioner at the same time. If you are supplying water pumps, be aware of a couple of things to watch out for (see photo on page 39). Different applications had a bypass nipple while some did not.

The best bet is to have the customer identify which pump they have. From ’88-’92 the water pump must have a locator pin at one end for the spring on the timing tensioner. The 1993 and later water pumps did not have the pin. The pin can be knocked out on new and remanufactured water pumps that have the pin if it is not needed for the later applications.