Work to do to my motor while it is out of my ca

[1998yellowstang]

I recently bought a motor from a wrecked 350z with 86k on it. I have the motor on a engine stand currently. The plan is to do the following while the motor is out:

1) Throughly clean and detail the motor
2) Replace spark plugs (possibly replace the coils depending on cost)
3) Replace the valve covers with a set of 04 maxima covers
4) Replace the knock sensor with a OEM sensor
5) Replace the knock sensor harness with one from z1 Motorsport
6) Replace the camshaft position sensors on both banks with OEM sensors
7) Replace the crankshaft position sensor with a OEM sensor
8) Install under drive pulleys and new belts
9) Install plenum spacer
10) Install catch can

Things I might do:
1) Replace water pump - anyway to check if it works while the motor is out?
2) Replace the front O2 sensors on both banks with OEM sensors
3) Install headers

What are your thoughts? Are replacing some of these parts a overkill? Is there anything else I should do while the motor is out that I'm missing? (within reason)

[evildky]

1. cleaning the motor is a good place to start
2. plugs yup might as well
3.I was gonna suggest the valve cover gaskets, if you plan to swap covers I assume you plan to do so with new gaskets
4. not a bad idea while it's easy-ish to get to
5. ? If you replace the stock sensor in the stock location your stock harness should be fine.
6. These aren't terribly difficult to get to in the car, I'd leave them.
7. Super easy to get to, I'd leave this guy alone too.
8. I'm not a fan of Underdrive pulleys but the belts are cheap insurance (you might want to check or replace the "idler" (read as tensioner but nissan calls it an idler)) also you can upgrade to the late 06 alt belt and spacer and delete the giant idler on the front of the engine.
9. easy to do anytime, cheap power.
10. I'm a fan of the stock pcv system, unless you are going turbo or have serious blowby there is no reason to add a catch can.

Stock water pump should be fine unless you have reason to suspect it, same for the o2 sensors, headers, well if you want to add headers it's a lot easier with the engine out.

This is also a good time to clean the engine bay, you'll be amazed how gunky the crossmember is. Look over your replacement engine real good, pay close attention to the timing cover and oil pan If anything is leaking now is your time to fix it. Pull out the dipstick, I helped a bud replace an engine and the boneheads he got the motor form replaced the oil pan first and when they did they sandwiched the dipstick, fortunately we found out before putting it back in. Use your wire harness. In my friends case the harness from what was supposedly the same model and year was not the same. stript he harness off the new motor, then swap it over from the old motor. We had multiple people working and the cam sensors got swapped in the process and put the ecu into lockout mode and took forever to figure out why.

[1998yellowstang]

Great advice! Thank you!

Can you elaborate on this? Do you happened to have a link or how to on this? " I'm not a fan of Underdrive pulleys but the belts are cheap insurance (you might want to check or replace the "idler" (read as tensioner but nissan calls it an idler)) also you can upgrade to the late 06 alt belt and spacer and delete the giant idler on the front of the engine."

[evildky]

Here is the shorter belt and spacer from Z1 http://www.z1motorsports.com/350_g35/pr ... ts_id=5640 Not much to it, although it's kinda tough to get the idler out and the spacer in with all the accessories on the engine takes a bit of finesse.