L24 block with L28 pistons - which head gasket to use?

[MKI4EVA]

Pretty important item to replace but I'm not quite sure which is the correct gasket.

Reason is I got an early L28 model one and it's nothing like the one already one the motor.

Thanks in advance.

[Diseazd]

L28 pistons won't work in an L24 block......not enough cylinder wall for that much overbore.

[MKI4EVA]

are you sure? I have P79 stamped on my pistons and it's definitely in a L24 block. Or am I missing something?

[Diseazd]

Are you sure it's an L24 block?

[MKI4EVA]

Yeh block code is L24XXXXXX.

I think.....hmmmm.

[Diseazd]

Look at the big number next to the driver side motor mount. If it says F54, it is an L28.

[MKI4EVA]

could just make out P30?

confused as ever:

ENGINE

DISPLACEMENT

BLOCK CASTING CODE

HEADS

L24 (1970 240Z) 2.4 liter # E31 (flattop pistons) E31

L24 ('71-73 240Z) 2.4 liter # P30 (flattop pistons) E88

L26 ('74 260Z) 2.6 liter # P30 (flattop pistons) E88

L28 ('75-80 280Z/ZX) 2.8 liter # N42 (dished pistons) N42, N47

L28 ('81-83 280ZX) 2.8 liter # F54 (flattop/dished pistons, siamesed cylinders) P79, P90, P90a

Edited August 26, 2012 by MKI4EVA

[Diseazd]

You may have enough metal to get the pistons in, but the remaining walls wouldn't have enough metal to avoid flex. Did the engine run? Did you buy it with this combo? If so, did it run and if so, how good? In my experience with Z's, I've never known anyone who put L28 pistons in a 240Z block. In the old "How to Modify" book, .080 inches was the maximum over bore recommended.

[bpilati]

You may have enough metal to get the pistons in, but the remaining walls wouldn't have enough metal to avoid flex. Did the engine run? Did you buy it with this combo? If so, did it run and if so, how good? In my experience with Z's, I've never known anyone who put L28 pistons in a 240Z block. In the old "How to Modify" book, .080 inches was the maximum over bore recommended.

That's cause they didn't use a piston shrinker.

[LeonV]

Mic the bores to know for sure, don't go off of stampings.