I look at a 1971 240z with an Engine Block number L24 015581. The head has a E88 Casting (which should be E31 for 1st series) and the valve cover I don‘t know. What are your recommendations? I was not able to check yet, if the block was mtching nrs...

Edited February 20, 20187 yr by Phentree

Welkom Phentree, why should it be a E31?  There were early cars with an E88 head.. for all i know.. 

Lots of good reading here:

 

 

So I bought the car :) Its a matching numbers 1st series manufactured in 10/70z Which according to http://www.xenonzcar.com/s30/engines.html. should be an E31. The nice part about it would be originality as well as best compression ratio of all the heads that would fit. Thoughts on this? Where to get it? I am currently in Japan....Thx!

Your car is right on the borderline where they changed over to the first E88. The change is somewhrre around oct - nov 1970, but some people have a seen them on 240Z in early jan 71. There is no real hard dateline when they changed over.  Even VIN numbers can be a little misleading.

If yours is still an original E88 head it will have basically the same specs as the E31 with a 44.2cc chamber iirc. Somewhere in August/September 71 they redisgned the ports and lowered the compression ratio on the E88 head.

A lot of debate on the E88 head and how many variations are actually out there. Some say 3 and others say four variations.

That’s interesting! is there a good post you can recommend on it? My L24 engine nr is 01558x... Wondering if there is a way to find out if that one was equipped with an E31 or E88?

FWIW - my engine (all of it) is original to the car.  It has  P30 block with a E31 head.