squareish

 

Square, not round. The round ones were the N-47 and the P-79.

 

Yes that's a round port head with steel valve seats..

 

Actually Steve, it could be a N42.


I have a BONE stock 77 early car, that has a N42 head. Some 77's had the N42's.

 

Okay, it IS a '77 and it IS an N42. 3 owner car from new, well documented, well cared for its whole life.
Who is speaking from experience, that is to say, who HAS an N42 and can verify round?

Thanks!

 

I can Verify that the N42 has Rectangle ports, and the N47 has round. I can also verrify that your car is possibly original with the N42.

 

Thank you 1 fast Z!

 

I can...

I can say EVERY N42 I have ever owned has retangular exhaust ports.

I have NEVER seen a round-port N42.

If the casting number is N42, I will lay money it's RECTANGULAR exhaust port configuration.

 

I'd imagine its possible for a VERY early '77 to have a N42.

 

well...

My Fairlady 280Z manufactured in July of 1978 had an N42 on it, and being this car still has all the Shaken-Sho seals on it, and a provenance traceable from almost the day it was manufactured doubtful that "79" ZX had an engine change---being it only has 43,000km on it!

Let's say "For the US Market" just to qualify that N42 talk.

The N42 was available in JDM vehicles for a looooooong time. They had several combustion chamber shapes along that path, as well (like the E88's and N47's)...

 

You're right, I read 77 and assumed N47. If it's an N42 it's square but could easily be a replacement engine/head as well at some point? Maybe the early 77's were still using the N42's? I've never seen a 77 that had a sqaure port head but that doesn't mean they don't exist. It does seem odd that they created that head to meet the 77+ emmisions standards yet would produce cars with the earlier head?

 

We aren't talking about what year car might have what head. Look at the side of the head for a casting number..............The N-47 and P-79 have round ports, and everything else, including the N-42, has square/rectangle ports.