A few days ago i purchased a 95 b18c2 integra that had the head pulled off for a head gasket replacement. Before putting the gasket on and the assembling the engine back together, should I clean off my pistons, valves, etc?

 

First thing is first, and anyone who has done alot of hg jobs will agree with me, that once you freshen up the top end, the bottom end will begin consuming oil. Happens all the time, and considering you bought a car that had the head off, **** has probably gotten down in the cylinder walls and rings.
With all that out of the way. If the pistons aren't hideous I leave them be. The valve faces will get washed clean after they wash your head when they resurface it at the machine shop. Hopefully the PO didn't overheat the motor badly enough to warp the block's deck or distort the cylinders or wipe out the bearings. Use A Felpro or OEM head gasket. grab an intake and exhaust gasket from the local auto. Dont forget plenty of carb cleaner and paper towels. Get the head gasket surfaces as clean as possible! Torque the bolts with a good torque wrench. Replace the timing belt, if your pockets are deep enough do the waterpump while you can get to it.

 

B18C2? I have never heard of this engine...

Is it true you need to replace head bolts to get correct torque spec?

 

No, these head bolts are not TTY and can be re used - Unlike D series headbolts. Although everyone and there brother has reused them countless times with success as well.