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HybridZ

Z heads, are they interchangeable?


akeizm

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My friend has a 280zx which is getting an rb30 put into it to replace the l28. The engine isn't that good, its chewing water but my question is.

 

I have a 260z with the flat top carbs and I was wondering if the L28 head with fuel injection would bolt onto my L26?

 

If not how hard would it be to modify the L26 head to take fuel injection?

 

Thanks Marc.

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I had exactly the same setup as you, flattop hitachis on a 260Z. I bought a intake manifold of a 280Z and adapted my block to take the manifold. The studs on the block are in a different position. this is how i did it.

 

Take a large enough piece of hardwood so you can cover it with a 280Z intake gasket. (something like a 2 foot piece of 2x4)

With a center punch you can mark the places where the studs should be. Some of them will be in the same place and others will have to be drilled in the head.

Now on a drill press drill all the holes in the wood.

Take out all the studs from the head that you will not use.

Slide the the piece of wood over the remaining studs.

If you drilled right the wood will slide in place and and can now be used as a guide to drilling the holes in the head.

Because you used a drillpress to drill the wood the holes in the head will be at straight angles.

At first i was scared that i might hit a water jacket in the head or something but this is not so. There is enough meat on the head to do this.

after you have drilled all the holes you must tap new thread in them.

 

Now for the second part.

Fuel injected heads have a little notch cut out of them to allow the fuel spray to hit the back of the valve. You can take an intake gasket from a 280z and use this to mark the places where the notches should be. Now grind out the notches. Be carefull as the head is rather soft aluminium.

 

It looks like a lot of work but I did it in less than a day.

 

Are you going to an aftermarket fuel setup? I went megasquirt and now get about 170 hp from this engine and good milage too (11km on 1 liter, you do the maths :wink: )

 

in the end it doesnt matter what you do as long as you get rid of those flattops.

 

good luck and let us know how it turns out.

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Reading about the megssquirt system sounds pretty cool, but I don't think my old man would really want to make an efi system.

 

But thanks for your answer xander.

 

Well how about the other question?

 

Can an L28 head go onto an L26 Block? (This really is the turning point for me. If yes, then i'm going to get EFI, if no then Hs6's it is)

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