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Discussion Starter · #1 ·
I am planning on putting a E-31 head into my 78' 280z.I am still using FI. I have heard that i will have to do some machine work to get the injectors to fit.

Has anyone crossed this head with FI? If so what work did you have to do to cross it over?
 

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The small valves need replacing to gain max power

The small gain in compression will not offset the loss of airflow capability unless you replace them with the larger valves.Also, the E31 lacks the proper bolt holes to use with your fuel injection manifold. Later,norm
 

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Discussion Starter · #3 ·
More Questions

So.... is there no way for me to use FI on an E31 head. What about E88? What would it take to convert a FI to Carbureted?

> The small gain in compression will not
> offset the loss of airflow capability unless
> you replace them with the larger
> valves.Also, the E31 lacks the proper bolt
> holes to use with your fuel injection
> manifold. Later,norm
 

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Discussion Starter · #4 ·
How hard to replace Valves on early head?

How hard is it to change out the valves in a older head? Have you done it? I am looking for High CR as well and was looking at a early head but worried about swaping valves. I have several extra valve sets from late model heads, Can I have a shop just swap them over? Also is the head dia. smaller than the L28 chamber? Does this cause and trouble.. hehe sory for all the questions..

Thanks

PinkZGirl
 

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Re: More Questions

It would take some careful drilling and tapping to make correct bolt holes,but I guess you could do it.As far as the injector hole, that would be done very easily with a grind stone to the head intake roof port.Also ,I do not believe any of the E88 heads were drilled for fuel injection manifold's.I would recommend you get a good N42 head and shave it at least .040 with a dished piston engine or just bolt it up to a flat top piston engine. Later,norm
 

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Re: How hard to replace Valves on early head?

> How hard is it to change out the valves in a
> older head? Have you done it? I am looking
> for High CR as well and was looking at a
> early head but worried about swaping valves.
> I have several extra valve sets from late
> model heads, Can I have a shop just swap
> them over? Also is the head dia. smaller
> than the L28 chamber? Does this cause and
> trouble.. hehe sory for all the questions..

> Thanks

> PinkZGirl
A good machine shop could change to the larger valve seats rather easily but I don't know the cost to install. The valves would be slightly shrouded by the chamber but you could easily use a grindstone to open the area up around the valves. As in previous post, I would recommend just getting a good N42 head and shaving it at least .040 with dished pistons or just bolting it up with flat top pistons.This head already has the larger valves, is easy to find and has good airflow characteristics. Later,norm
 
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