I recently purchased a 22r with the 20r head,has an rv cam,22r valves,timing chain cover was machine to acommodate dual chain and power steering pump.When adjusting the valve lash the tappets are at the end of the threads.Not much for th lock nut to grasp.Also noticed the chain is too loose. What can I do about the tappets? From what I've read the valve train(rocker rails) assemblies are interchangeable. I compared the valve train in my old 22r head and it looks identical.Please help a 'newby' out. Thanks for any help.

 

I'm actually researching this right now as my 20R head is at the machine shop waiting for my decision.

Searching around here and pirate it looks like the 22R valve is shorter than the 20R. Either some major machine work has to be done to get the valve deep enough for the stem to be at the same height, or the geometry is off.

Maybe the OP has this problem? Does anyone know more about the swap. I also have some concerns about shrouding. It doesn't seem like there is much to gain just putting in a bigger valve, the intake port is the same size, that seems like the bigger restriction to air flow.

Any thoughts? Is there a better valve to use? Stay stock?

 

I ended up taking the head to the machine shop. The machinist sunk the valves deep enough to solve the lash problem.(cost 80 bucks) They were noticeably above flush in the mixing chamber.I suggested putting in 22r seats, but he was concerned about running into weaker casting in the area around the seat and ruining the head, so he just machined out the 20r seats enough to get the stem length needed to adjust the valves. The previous machinest didn't know what he was doing. I have only put about 120 miles on it since I got everrything together. All seems ok except for running rich due to the elevation (7000 feet) here.I don't know what your situation is, but if I had to do it over I would have rebuilt my 22r back to stock.Maybe add a more radical cam, add headers, etc.Good luck.