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Old 05-28-2021, 02:17 AM   #60
irax
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Quote:
Originally Posted by Irace86.2.0 View Post
I don't think the FB25 platform is compatible for many reasons besides the starter. The FB25 has a longer stroke and likely has a difference in block dimensions, so heads and intake manifold are likely not going to line up. The FB25B also has 10.0:1 compression, and it doesn't have direct injection. The FB25D has direct injection on a 12.0:1 compression, but still, it would be better to do a FA24F block swap or FA24D engine swap than attempt the FB25.
The fb25 and fa20 blocks are exactly the same in outside dimensions. Its just a matter of swapping cranks and con rods. Fb25 94mm pistons with 86mm stroke equates to 2.4 litre.

FA20 heads on an FB25 block will raise the compression a little bit. Thats why i said 10.5:1
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