Originally posted by Slacker
This is prob a dumb question, but if I do bore my engine for more displacement will that degrade the stregth of the block?
No it won't degrade the strength of the block.
Here's how boring out works. You have your piston sleeves that the pistons slide through. When you bore out the sleeves are bored out to a larger diameter. If you keep stock sleeves then you shouldn't overbore more than .5mm (or .020"). However since you'll be putting in (for example) GE or Darton ductile iron sleeves then you can go from the stock bore of 81mm to 85mm! If you do that to a B16 you'll effectively change your engine from a 1.6L to a 1.8L!
So...boring out your future iron sleeves won't degrade the integrity of the block. Since they're iron sleeves they're SUPER strong. So boring them out won't weaken them.
BTW, I believe Darton and Eagle sell sleeves that come prebored out to 84mm (the stock B20 block bore). So then you can over bore those sleeves to 85mm (that's .040" over). This overboring principle/info will work with any B series engine.
Hope this helps.