I have a 96 outback that is beginning to have some lower end noise. Not sure if it is piston slap, rod knock or wrist pin, so I am think ing of building another motor for her just in case.

 

Can I mate and ej22 block to ej25 heads? If so, are there any issues that I need to know about or should I just look for an ej25 block with lower miles on it?

 

Thanks

bump

yes, but it will result in a slightly lower compression ratio, so combined with the lower displacement the power loss would be pretty noticeable. The only thing you need to do is use 2.5 headgaskets.

Your compression ratio will drop into the mid to upper 8.*:1's IIRC. So you will drop a good bit of power.

 

You can run a complete ej22 in place of the ej25 without any issue, other than egr system.