n42 vs n47 maxima head

[motorsci]

I have 2 cylender heads the frist is a n42 the second came off a 77 810 /maxima. I cc both the maxima n47 was 37cc and the n42 was 42cc. I understand that the n47 maxima head will yeald higher C.R . My question is what is the difference in the combustion chambers? The threads I have read hype this head as having a better combustion chamber or that its like a p79/p90 head. after looking at both heads side by side I see little or no difference in the combustion chambers. I compared the n47 maxima head to a 280z n47 the 280z had larger intake valves and roughly 44 cc so the do aper to be differnt heads with the same casting number.

[1 fast z]

Can you post pics?

[zcarnut]

Some clarification is necessary:

 

There are two different N47 heads for the 810 and Maxima. The early N47 head was used in the 810 and the later (the preferred one) one was used in the Maxima. Both heads are marked N47 and appear identical externally. For the later N47 head Nissan changed the shape of the combustion chamber from a “dome-wedge†shape to a “wedge†shape.

 

The 810 was built from 1977 to 1980. The 810 evolved into the first generation Maxima which was produced from 1981 to 1984. People assume that “810 = Maxima†and vice versa, which is not necessarily true.

 

So, what you have is a “810 head†and not a “Maxima headâ€.