So i understand that the Neutral Balance Shafts in your lsj balances the rotating assembly within the motor, but where exactly are they located in the engine? say i had a light weight flywheel and was up grading my valve springs for more high rpm capabilities, are these shafts worth upgrading as well? and i have access to a machine shop, is it safe/possible to lighten my factory shafts? any info on this topic would be greatly appreciated.
thanks
jeff

 

they are in the left side of the engine on the block and i believe they are attatched to the timing chain belt

 

are they easyily acessable? or would it require semi to full motor removal?

 

They can be installed with the motor still in the car. It will take some negotiation with a picker, but it's doable.

They are inside the block, and run parallel to crank on each upper side. Both chains and most of the guides behind the front cover will need to be removed.