E88 not the best head?

[71datsun240z]

hi all i was told that the E88 head was 2nd best. if im wrong correct me please but is there a better head if so where can i buy it? let me know plz and thanks

[hmsports]

2ManyZs enlightened me last week that the E-88 can be made better by milling it down to raise the compression some.

Most racers swear by the E-31 and that's what the major engine builders use. They are getting harder to find.

Hope that's what you wanted.

Rick

[Zvoiture]

In these days of scarce E31's....N42 seems a good 2nd choice.

steve77

[Royce]

Time to stir the pot a little. What is an E88 head? I have heard conversations from respected Z folk that there are actually 4 different E88 heads on US model Z cars!

Here is the way it was explained to me (corrections are welcome). Heads with the E88 stamped on them started around 01/71 with the series II 240Z(or late '71 model.) This head is supposed to have the same combustion chamber as the E31. Then, in 09/71 with the series III 240Z('72 model year) the combustion chamber was changed to slightly lower compression design. Next, with '73 model year the E88 head was further designed for lower emissions and finally in '74 larger exhaust valves, same size as 280Z, were put into the E88 head.

I do have several of the E88 heads on spare engines but have yet to take them appart to see if I can document any noticable differences. I myself have a hard time believing there are 4 E88 heads but have found documentation of at least 2 different E88 designs.

So which Z head to use- E31, E88, N42, N47, P79, P90 or P90A. Did I miss any? First, unless you plan on changing to round port exhaust you can rule out the N47 and P79. Next it depends on which block/pistons you will be using. If using 240, 260, 280Z block with stock crank, rod piston setup then forget the P90 & P90A unless you are going to run a turbo because the compression would be too low for performance driving.

So that leaves the E31, E88 or N42. None of these are a "bad" choice, with the exception being the emissions designed E88. But trying to identify an E88 head may be a challenge.

So that narrows us down to E31 vs. N42. The E31 is supposed to benefit from a slightly higher compression combustion chamber design but because of age and limited quantity finding one in good condition can be difficult and expensive. The N42 is slightly lower compression combustion chamber design but unlike the E31 and early E88 it has larger exhaust valves and came with hardened valve seats and guides for running unleaded fuel. Plus, there are lots more available and you can shave them to get higher compression if that is desired.

Bottom line, I am guessing that the difference between the heads may be +/- 10 HP. Unless you head is damaged you would probably get more by setting your valves correctly, getting a valve job, changing the cam, recurving your distributor or porting and polishing your head and intake manifold then by searching for a new head. But it really depends on your desired results and how much $$$ you want to spend.

Sorry for the long post! I hope it makes sense and is helpful!

[Dan]

I have two different E88 heads, the early E88 head and a later one (atleast this is what i've been told). The casting marks are different between the two and makes idetification abit easyer. The early head has a skinny E and a uniform 88 casting mark where as the later head is uniform through out the three characters (same size and thickness). The early head has notches at the bottom of each combustion chamber, and i'm told the early head has the same compression as the E31. I'v also been told that it's an easy swap to put in the larger valves in the E88 heads, has anybody done this before?. I have the early head on my 240, which i recently put on. I changed the trans and rear end too at about the same time so i couldn't say if the early E88 head gave me anymore HP than the later one. I will say that the 5 speed 3.90 R200 and Supposed high compression E88 head have made a big difference.

[Royce]

Hmmm... I'll have to take a look at the casting numbers on the E88's I have.

Regarding the valves. My E88 had been fitted with 280Z valves. I believe it is relatively simple machine work because if I remember correctly the original smaller valve seats can be machined to fit the larger valves. In other words they don't have to change the head itself. But probably best to check with Rebello or another Z engine builder to be sure.

Have fun!

[71datsun240z]

thanks man the long post was needed to justify the question i asked was a big help in deciding the head i should probably go for. now the only thing that lies ahead is what Z had the E#! head on it im willing to spend the money to get it but i dont know where to start looking. also how much would a head like that cost? i tried to budget out the money for the car and for each area of the car that i wanna focus on.

also does anybody know where i can get a 77 280z 5 speed tranny? because i want to get one for my z while i have my engine out of my car.

[hmsports]

I've been told that a good E-31 head - bare - would cost me about $150.

[71datsun240z]

bare meaning what? like what else would be needed so that it would be ready to be set onto the lower block and ready to run?

what would a ready to run e-31 head cost me? d oyou think?

[hmsports]

What I mean by bare is just the casting - no valves, springs, cam, rockers, etc.

You can get a complete Rebello E-31 head for between $1500 and $2000. My stock E-31 rebuild cost me about $800 - but I had the casting from an old engine.

It's very hard to say what a complete head would cost - and what condition it would be in. Just start posting and searching the internet. I'm sure someone on this site has one they wouldn't mind parting with.

Sorry I couldn't be more specific.

[hmsports]

Just got a line from Zed where there are three E31 heads for sale - all around $150 - go here

[71datsun240z]

nah dude every little bit helps i thank your for the info =)