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I am currently investigating swapping a FB25 2.5 liter block into my 2014 XV. I would keep all the original heads, accessories, wiring from the FB20. It seems I can find FB25 blocks for around $400-800 on ebay. For those that have had their blocks apart would the FB20 heads and accessories fit on the FB25 block?

Thanks,

Tony
 

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The 25 has been bigger bore and th ports are likely different. Today's engines are made for max mpg do even if it fits. Forget it
 

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This can be done. I have a 2.5 block at the moment. The main mechanical issue is that the 2.5 pistons need to be machined so they clear the smalller 2.0 combustion chamber.

With 2.5 head gaskets, you should be able to run 92 octane fuel....final compression ratio with 2.0 heads in over 11:1.

You will need to scale the load.maps.in the ecu also.

Needs 2.5 injectors too.

I have a hybrid 2.0/2.5 tune running on my 2.0 at the moment.

Now just need to do the block swap.
 
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