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Discussion Starter #1
I just picked up a 280zx motor from the junkyard. It is a f54 block
and a p79 head. It has 60k miles on it. My 73 240z has 165k miles
on it and it is l24 with e88 head. I am definately using the new
block in my car, but am trying to decide which head to use. I am
going to still use the SU's and headers.

If I use the p79 I am going to have to buy new headers for the round
exhaust ports ($200). If I use the e88 it may need some
reconditioning. I compression tested the l24 and the fourth
cylinder's low compression did not raise when I added some oil, so I
assuming it has some kind of valve problem. I have also heard that
if you are going to use SU's with a p79 you can't use the stock cam.
It looks like it is going to at least cost $500-$600 to use the p79.
It should be less to recondition the e-88.

My question is before I start investing in one or the other which
should I use?

Thanks
 

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I responded to your first post. My cam cost around $250 new grind. Let me know if you want more info.

Chris
 

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Hello
I am in the same place you are.
I just put in a 81zx motor with a p79 head in my 71z , I am using the stock cam and the p79 head exaust manifold, the car is in the muffler shop having 2 exaust put on and a exhaust flange from a 280 motor since the early flange won't match up with the 280 exhaust , got it at the local junk yard for $5 , the price for the exhaust is $160 cheaper than a header , I have not had a chance to run the car much so I will let you know how it turned out, I think the carbs will work fine though
 

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> I just picked up a 280zx motor from the
> junkyard. It is a f54 block
> and a p79 head. It has 60k miles on it. My
> 73 240z has 165k miles
> on it and it is l24 with e88 head. I am
> definately using the new
> block in my car, but am trying to decide
> which head to use. I am
> going to still use the SU's and headers.

> If I use the p79 I am going to have to buy
> new headers for the round
> exhaust ports ($200). If I use the e88 it
> may need some
> reconditioning. I compression tested the l24
> and the fourth
> cylinder's low compression did not raise
> when I added some oil, so I
> assuming it has some kind of valve problem.
> I have also heard that
> if you are going to use SU's with a p79 you
> can't use the stock cam.
> It looks like it is going to at least cost
> $500-$600 to use the p79.
> It should be less to recondition the e-88.

> My question is before I start investing in
> one or the other which
> should I use?

> Thanks

Here's what I think. The P79 head has much better combustion chambers than the E88. However the E88 has better exhaust ports and will give you a higher compression ratio with the 280ZX block. If I am correct, that block has flat top pistons. You should have about 10.2 to 1 c/r with the E88 head. The p79 will be 8.8 I think, can't remember as there are so many combo's. I would decide on your compression ratio, then that will tell you what head to use. Personally, I would go with the E88 as I like a higher c/r. Makes for great throttle response.
 

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> Here's what I think. The P79 head has much
> better combustion chambers than the E88.
> However the E88 has better exhaust ports and
> will give you a higher compression ratio
> with the 280ZX block. If I am correct, that
> block has flat top pistons. You should have
> about 10.2 to 1 c/r with the E88 head. The
> p79 will be 8.8 I think, can't remember as
> there are so many combo's. I would decide on
> your compression ratio, then that will tell
> you what head to use. Personally, I would go
> with the E88 as I like a higher c/r. Makes
> for great throttle response.

Does anyone have an opinion os the N24 head someone knowledgable told me that this is a rally good head .
 

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> Does anyone have an opinion os the N24 head
> someone knowledgable told me that this is a
> rally good head .

The n42 head is pretty good. It has the 44mm/36mm valves and fairly good ports and combustion chambers. I have a friend who had an L28 motor built with an N42 head. All he had was flat top pistons, and header. He used stock carbs, cam, valve train and no porting. His car did a [email protected] with a 4.62 rear end. Now that's a lot of gear, but his motor ran VERY well.
 

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> The n42 head is pretty good. It has the
> 44mm/36mm valves and fairly good ports and
> combustion chambers. I have a friend who had
> an L28 motor built with an N42 head. All he
> had was flat top pistons, and header. He
> used stock carbs, cam, valve train and no
> porting. His car did a [email protected] with a
> 4.62 rear end. Now that's a lot of gear, but
> his motor ran VERY well.

Thanks Ian. That very setup has been suggested to me before with the suggestion that I use a mild Stage 2 cam from Crane. The only thing different is that my engine is fuel injected. I don't know how that effects it,if at all.
 
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