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Only good place is to look in the service manuals for those years.

 

Most things (crank, rods, pistons) swap freely from 96-98 in the 25D. These will not swap into 99-later blocks. Pistons might, but not totally sure on that.

99 - later, the biggest change was with the crank, the thrust journal moved, and the rod bearing journals were bumped up from the 48mm to 52mm. That stayed mostly the same for about the next 10 years. People swap crank, rods, pistons from STI 255 turbo blocks into the 251 and 253 blocks fairly regularly.

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Only good place is to look in the service manuals for those years.

 

Most things (crank, rods, pistons) swap freely from 96-98 in the 25D. These will not swap into 99-later blocks. Pistons might, but not totally sure on that.

99 - later, the biggest change was with the crank, the thrust journal moved, and the rod bearing journals were bumped up from the 48mm to 52mm. That stayed mostly the same for about the next 10 years. People swap crank, rods, pistons from STI 255 turbo blocks into the 251 and 253 blocks fairly regularly.

 

I am building an 07 2.5 sohc... all the blocks i have are toast.  Mainly trying to figure out if an 03 block and crank will work with the 07 pistons.  

 

Only good place is to look in the service manuals for those years.

 

Most things (crank, rods, pistons) swap freely from 96-98 in the 25D. These will not swap into 99-later blocks. Pistons might, but not totally sure on that.

99 - later, the biggest change was with the crank, the thrust journal moved, and the rod bearing journals were bumped up from the 48mm to 52mm. That stayed mostly the same for about the next 10 years. People swap crank, rods, pistons from STI 255 turbo blocks into the 251 and 253 blocks fairly regularly.

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The one main thing to match on the block is the way your PCV valve mounts.  There are 3 styles: a pressed in plain tube, a threaded tube and a sort of J-shaped mounting (California spec).  Matching that will make your life easier. 

 

Other than that, I don't believe there are any major block differences.


Emily

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PCV stuff can be worked around with various fittings, hoses, etc.

If the block has the thread in-fitting, go to the dealer and get the PCV valve for that year, and get the hollow fitting that goes in the manifold to match.

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