[Max Capacity]

My 18 3.6R has been on Amsoil doing 10,000 mile oil changes, never had to add oil during that time.
Now my 05 Legacy GT with bigger turbo tuned at 21psi, seeing redline or above weekly, I kept a close eye on oil usage and added as needed. But the car was fun to drive. That also was on Amsoil doing 7-8000 mile oil changes. That engine is still going strong at over 160,000 miles on the short block.

The 18 is driven differently. It's never been to WOT. (wide open throttle)