Im building a b20b block for a b20vtec build. New rings and pistons are going in. Should I hone the block before the pistons are seated?

The Helms manual says "Only scored or scratched cylinder walls must be honed".

 

of course you hone them, it gives the new rings a new surface to become friends with.

 

While having the chance its good to hone the cylinders. Whether you "need" it or not, you want the lease blowby

 

Tell the machine shop to just bump the cylinders for new rings and they should know what theat means. If after market stock size pistons are used Arias/JE etc... then tell them to power hone. Im a machinist and thats what I would recommend.

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