3rz valve job

i wanna replace the valves, springs cams and everything else in there what are the best options for that?

 

Unless something is wrong with your valves, don't do it. The 3rz is a great engine, but it's a bit like an Apple device, it's well designed in the hope it'll never need to be taken apart, because if you need to take it apart it's a nightmare. The valve adjustments are the only thing you should have to do outside of usual fluid changes.

To replace the valves you have to remove the head, to remove the head you need to remove the timing cover, to remove the timing cover you need to remove the oil pan, to remove the oil pan you have to either disconnect the engine from the transmission and jack the engine up or remove the front differential. I'm not exaggerating, doing a head gasket is more difficult than on a 5vz V6.

If you legitimately need to replace the valves, follow the guides on replacing the head gasket because you'll need to do all that. I'm not sure about replacing the valve springs, but I'd only mess with what is wrong.

 

yeah i have low compression and i was reading that i would need to replace the valves cause they probable weren't seated right. i don't mind doing the work to it i have all the tool necessary ive just never worked on a Toyota before besides like breaks and small things.

the first and second cylinder has 121 on the compression and the 2 back have 90. do you think i would just need a valve adjustment?

 

Check that first, but you'll likely find that your exhaust valves are burnt. This is pretty common when this engine gets high mileage. I would send the head out for valve job and have the head surface machined. The camshafts and springs are probably fine.

 

You should also try adding oil to those cylinders and recheck compression.