I am the original owner of a 72 (built in 71) 240. The head has been reworked (butched) twice. It needs new seats, valves etc.

Any help or advice is welcome. It still has the orginal brass seats. Also, can an E88 head casting replace the earlier one (I believe E81)?

Originally posted by JoeT

I am the original owner of a 72 (built in 71) 240. The head has been reworked (butched) twice. It needs new seats, valves etc.

Any help or advice is welcome. It still has the orginal brass seats. Also, can an E88 head casting replace the earlier one (I believe E81)?

The early 240Z's came with an E31 cylinder head, and YES, an E88 head can be substituted. Be advised, however, that there are TWO varieties of E88 head. One came on the very late 71 240Z's and the very early 72 240z's. This head had combustion chambers of similar size to the E31 (a high compression design). The later E88 head came on the late 1972 240Z's and the 1973 240Z's. This variety of E88 had significantly larger combustion chambers (low compression) and was designed to meet the more stringent SMOG regulations that were imposed on new cars. Both heads will fit the block, but you will get different (lower)performance with the late version E88 head. The only way to tell the two apart is by examining the combustion chambers.

See picture below. It shows the early head; E31 or EARLY E88, that area indicated is "notched" or filled in on the early heads resulting in a smaller combustion chamber on the E31 and EARLY E88.

In the later E88 the combustion chamber would be "more round", in other words, the notch of metal would be missing, giving a larger combustion chamber.

The E88 head will replace the older E31 head. They will be a direct swap. Although you will lose some compression with the E88 head over the E31. The E31 heads have a higher compression.

Thanks for the info. It has jogged my memory. If my memory is correct, finding an E31 or early E88 isn't easy. So it looks like I'm going to have to get mine redone in order to keep the car's stock performance. Plus I remember that the late 72's and 73's were hard starting when hot. Maybe it was partially do to the different head ??

JoeT

The starting problem was due to the flat top Hitachi's. Since you will have the round top SU's you will be fine even with the E88 head. Look for some parts cars. Classic Auto Trader has a couple of cheap (750.00) cars with the E31 head. They don't run, but the head might be in better shape than your. Plus, you will have some parts from the car.