Different Early E88 Heads ?

[superfunk]

Ok, if I look around the internet I find alot of different comments about E88 heads. I know that there were early e88 heads that were similar to the e31. The way to tell is by the notch around the spark plug. But I seem to have two of them that have different combustion chambers. Any insights?

[Carl Beck]

The earliest heads marked E88 came on the last of the Series II - 1971 Late Model Year 240-Z's, and the first of the Series III 1972 Model Year. They had the exact same 42.4 cc combustion chambers as the E31. Very rare to see them anywhere today.

The E88's that came on the regular production Series III cars had the same combustion chamber shape but they were 44.7 cc. Slight compression loss from the E31's but better flow.

It would seem that you have one of the two above - you'd have to have cc'd them in stock condition to determine which was which. (no matter really at this point)

The third E88's came on the 73 240-Z's - redesigned combustion chambers to meet the Emissions Standards and 47.8cc's .. The fourth type came on the 74 260-Z's here in the US ... 47.8cc with larger exhaust valves. Again Emissions Heads.. uck...

The head you have pictured - with the valves in place - would seem to simply have been reworked already. Looks like larger valves were installed and the valves were un-shrouded. The head with no valves installed would see to be just clean 71/72 E88 (depends on the cc's).

You need to cc the combustion chambers at this point, for either or both heads - to assure you are within whatever compression ratio you want to be running.

FWIW,

Carl

[onuthin]

The earliest heads marked E88 came on the last of the Series II - 1971 Late Model Year 240-Z's, and the first of the Series III 1972 Model Year. They had the exact same 42.4 cc combustion chambers as the E31. Very rare to see them anywhere today.

The E88's that came on the regular production Series III cars had the same combustion chamber shape but they were 44.7 cc. Slight compression loss from the E31's but better flow.

FWIW,

Carl

I have 3 e-88 heads from mid 71. I also have 2 e-31 heads from early 70 model. Is there enough difference in the two to make difference? Ronnie

[Carl Beck]

Years ago - like back in the mid to late 70's I talked with the guys from Bob Sharp Racing when they were here in Daytona. All I can tell you is what they told me at the time... The earliest E88's had improved castings - so they were less likely to crack around the exhaust valve seats. The second type of E88's had the improvement castings around the exhaust valve seats and improved curvatures as well as smoother castings in the intake and exhaust ports that helped improve the flow.

I have never found any Nissan documentation supporting this, but both Bob Sharp Racing and BRE ran the E88's on their L24's from 72 forward.

Over the years it seems that the main problem with the E31's has been the fact that they do tend to develop cracks around the exhaust valve seats. So if you plan to use one be sure to have it checked before putting additional money into it.

FWIW,

Carl B.

[madkaw]

I believe Carl hit the nail on the head . The first pic looks just like my early e-88 head with bigger valves and the chambers unshrouded.As far as which one is better there are a lot of opinions on that but the first head looks like it's ready to go

[superfunk]

Thanks,

I am going to go with the first one, mostly because its built and ready to go.

[deadflo]

Ok, if I look around the internet I find alot of different comments about E88 heads. I know that there were early e88 heads that were similar to the e31. The way to tell is by the notch around the spark plug. But I seem to have two of them that have different combustion chambers. Any insights?

Can you elaborate a bit about the notch around the spark plug?

[superfunk]

You'll notice that the casting comes into the combustion chamber a bit around the spark plug, on all the head pics that have been posted so far. On the later versions of the E88, this was left smooth. That is to say that the profile stays round in the spark plug area and there is not notch into the combustion chamber.

[onuthin]

The second type of E88's had the improvement castings around the exhaust valve seats and improved curvatures as well as smoother castings in the intake and exhaust ports that helped improve the flow.

FWIW,

Carl B.

I just pulled the intake manifold off an early E-88 head.I ran my finger inside the intake port and there is about a 1/4 inch lip where the gasket is to small for the opening.Just a question but wouldn't it help if that exess gasket was cut out to the same size as the port?It seems like it would allow better flow thus more power. Ronnie

[=Enigma=]

Pure laziness.....Yes, that's just one small part of port matching. You also want the intake outlet on the manifold, and the intake inlet on the head to match up as closely as possible.

[Phred]

This one has had a little work done to it, but you can see how the area around the spark plug has been filled in on the last E88 open chamber design. Carl Beck; can you confirm that this style is indeed the last of the E88 chamber designs?

Phred