Still in the crate. Has odd exhaust ports. Has anyone seen this before?

Also has an odd "temperature sensor bung" that looks like it was welded on. Maybe for use in the 280ZX? N42 heads didn't use the cylinder head temperature sensor.

Bring a Trailer

No Reserve: Datsun L28 Crate Engine

Bid for the chance to own a No Reserve: Datsun L28 Crate Engine at auction with Bring a Trailer, the home of the best vintage and classic cars online. Lot #190,091.

Already $1800. I'm surprised it's that high considering it's been sitting and you really don't know what you've got until you take it apart.

Is the compression ratio a turbo level compression ration?

Somebody called datsunparts bid $2200. There's a business called datsunparts, looks Roadster focused. Might be worth more parted out. Those exhaust ports are weird. Maybe it's a "detuned" L28 for a different model. Maybe the Z's got the good stuff.

https://datsunparts.com/

I don't understand what's weird about the exhaust ports? I thought they went round with the 280Z where earlier cars had rectangular exhaust ports.

Looks like N42 to me. I might be incorrect

Here a pic of my euro N42 head and N42 engineblock.. (Year is 1979.)

On 4/26/2025 at 4:43 AM, Zed Head said:

Has odd exhaust ports. Has anyone seen this before?

@Zed Head I often see those gasket and oilseal sets for the L24-L28 engines, they have round, square and diamond shaped exhaust outlets so i'm not surprised to see those round ones.

(The diamond called one is a hexagonal exhaustport.)

I asked myself if it's normal that there is paint within the oilfilter cavity, but my 1979 N42 has it also.. BUT..

There should NOT be any paint on the contact surface of the oilcardridge !! 😀 so that new engine is a fake?? Blue paintwork also does not look as if it's 40+ years old! (I got a new painted block in my garage under a cover and was painted new in 1990.. it does not look that fresh! AND It was under a thick cover all these years! )

ALSO, the original painted block has no paint on the waterplugs! (AND many other contact points, see pic in above reply)

Who sees more differences.. (Besides the sensor welded stud near the sparkplug 5 hole.)

Edited 7 hours ago7 hr by dutchzcarguy

Over on hybridz there's a thread of an N42 with round ports and the bung on the plug side of the head. The thread does mention ATK which this engine has a ATK sticker on it.

HybridZ

Identify this N42 head - round port???

Alright L series engine gurus - need help. identify this head! Its a N42 head, but it has external oil squirters for cam and ROUND ports! And one bracket on the side that is not common on L series...

That's good info. The OP was in Lithuania. I wonder if Tony D's explanation was half right except that maybe Nissan produced modified castings for sale to rebuilders or for their own rebuilds. Tony D suggested that the ports were welded and machined but the casting sprue suggests that they were cast that way. I'm no expert but I don't think that you could cast molten aluminum over old castings and get a good bond, besides trying to match properties and the post-machining involved.