Why would a chevy 350 burn oil on one side of the engine only?

i have a 87 chevy 350 i just put a crank kit in and has true dual exasut on it and it burns oil on only the driverside of the engine. no smoke comes from the passenger side exaust pipe. only the drivers side. what can cause this?Why would a chevy 350 burn oil on one side of the engine only?
Rings on the drivers side aren't seated correctly and oil is blowing by. or maybe the pistons and rings aren't correct for the bore.Why would a chevy 350 burn oil on one side of the engine only?
bad rings on that side
Bad valve guides, bad rings or stopped up oil return hole at the rear of the head. The stopped return hole is a no brainer to fix, just run a wire downit to clear it. Bad rings should show up on a compression check. If both of those check out then it could be bad valve guide(s).
bad rings or bad valve stem seals will cause this too happen,also if its been ran hot that will cause it too,there's many things that can actually cause it ,you may have to tear in to it to find out for sure,good luck on it.
The rings and or valve guides in that one side are suspect. Do a cyl leak down test on all cyl and that will narrow it down. Good luck.
Your oil rings on the driver side are burnt out.
before you condemn the rings...check the intake gasket on that side. if its sucking past the gasket to the underside of the intake it could be burning on one bank only. are you getting oil soakings on 1-3-5-7? valve stem seals???