I’m ordering a catch can for my Toyota pickup with a 22r (carbureted) engine. I was wondering if it would be ok to have just a breather on the catch can, and not run a hose back to the intake.
You can, but make sure to cap off the original connection the black hose was supposed to connect to on the intake side to prevent air issues.
The hose going back to the intake is a vacuum hose used to operate the PCV valve. The 22R engine has two vents in the valve cover. The one in the rear is for the PCV valve and power brakes. The one in the front simply runs into your air cleaner. You can't just cap off the fitting on the intake manifold. If you want a catch can, put it on the fitting on the front of the valve cover, not the rear.
Why not just run two filters on the valve cover and eliminate the pvc valve? Then you only have to cap off the vacuum connection that operated the pcv valve like Razmig said. Check out the engine pictures on LC Engineering. They all run two filters on the 22R/RE engines.