Using the bypass also pumps the oil more, marking more heat.

The ER pulley is the way.

 

It is definitely one way of doing it.

 

How long does it take to install the ER pulley and what other equipment is needed?

How long would it take to install the adjustable regulator?

 

($300 to $425 minus shipping) ER Pulley is $180 plus you have to buy adjustable cam gears at ~$125/per (EVO 8 requires intake/exhaust and EVO 9 requires exhaust only)
You have to remove the upper and lower timing covers and trim the lower timing cover to clear the pump pulley
You have to remove the valve cover to replace the cam gears
Probably 4-6hrs of work

Under $100 and takes about 20 minutes to install. You just remove the factory cap from the bypass spring and screw on the new adjustable cap, which is located on the oil filter housing. You then would need to drive the car to see what pressure you have and then adjust accordingly. Adjustment is just loosening the lock bolt and then adjusting the screw with an allen head, which is done without exposure to oil as it would be an oring seal on the adjustment screw. It is easily accessible from the bottom of the engine without removing anything and below is a pic of the cap circled in red.

 

Hats off to you Sir for taking the time to work on the bolt on adjustable regulator @ 240Z TT . Great Concept! I ported my bypass to lower oil pressure slightly years back.

I think both ideas are cool for a sub 8000/8500 rpm 4g63 engine to lower some oil pressure.

Beyond that RPM or for the road course , I think slowing the oil pump down with the ER gear makes sense. Extend pump life, slow down pumping oil to the top of the engine or letting it bypass and add heat.