The last picture is of the cylinder head. Is the mechanic saying there is a tube missing down the right side of the cylinder head? On the later cylinder heads the valve train is oiled from the internally drilled cam. The little holes in the cam lobes. There is no spray bar on the later heads like on the earlier car.

Patton is correct. You can see the small oil outlet holes in the cams.

I wonder if that's a non-US market L28.  They kept carbs in the rest of the world for quite a few years after the US market went to EFI.

You have the mechanical fuel pump mounts, for carb'ed engines, along with the self-oiling camshaft that came in about 1977 in the US market.  Here's a picture of the boss for the pump, but unmachined, on a 1978 US market engine.  A snip from your picture follows.

Or it might just have had a cam swapped in.

My 78 head number is 247788.  Yours is earlier.  Could be a 75 or 76 US market head head which still had the spot for the pump, but used the spray bar (oil tube).  Or a 77 head, which was the transition year.

5 hours ago, Patcon said:

The last picture is of the cylinder head. Is the mechanic saying there is a tube missing down the right side of the cylinder head? On the later cylinder heads the valve train is oiled from the internally drilled cam. The little holes in the cam lobes. There is no spray bar on the later heads like on the earlier car.

Yes, sorry the cylinder head, I am learning as I go on this project, the mechanic is saying that there is a tube missing down the right side of the cylinder head. So in your opinion this an a later model that has little can holes and is not missing a small tube or spray bar? 

Thanks

Here's a shot of my E88 with the early spray bar attached and the newer design laying beside it.  The newer one came off an N42 head that was changed to a newer oiler cam.  This was a common upgrade from all I've read.  Those spray bars a problematic and should be checked often, like every oil change for my 240.

240 spray bars...

280 with a oiler cam...

6 hours ago, Jon Dickson said:

Yes, sorry the cylinder head, I am learning as I go on this project, the mechanic is saying that there is a tube missing down the right side of the cylinder head. So in your opinion this an a later model that has little can holes and is not missing a small tube or spray bar? 

Thanks

Correct. Your version of your head and the cam does not require the oiler bar. 

For more info on heads. http://www.zhome.com/ZCMnL/tech/head.htm

 

Edited March 25, 20196 yr by scotta
Additional info

Make sure the cam tower's oil holes on the side are blocked off (in case they are the early type for an oil bar).

The cam towers look to be the early type. You can see the bolts just sticking out. Someone may have been running both the internally oiled cam and the spray bar. You need to block off the cam tower spray bar locations. Also on start up you need to verify that the cam is oiling. Don't assume it feeds oil out all the holes, verify!

On 3/7/2019 at 10:02 AM, Jon Dickson said:

 I purchased the car from my uncle while I was in high school in 1997.

I had the rust replaced and body work completed as well as the engine rebuilt before leaving it my parents garage for nearly 20yrs.

I don't have the original engine as of now, it has a 280 dual carb engine and has had that since I purchased it.

I was told that they used to race it in Japan, someone brought it over to WA state, my uncle bought it from him in the early 90s and I bought it from my uncle.

 

On 3/8/2019 at 7:56 PM, Jon Dickson said:

I couldn’t find the engine tag (must have been removed when it was last painted and must have it in a box somewhere) but the VIN that I did find on my old insurance card is S30100541. How do I determine what type of engine I have in there now. I know it’s not the original and I know it’s from a 280. The car is a five speed and the engine is a dual carb.

 

 

19 hours ago, Jon Dickson said:

I went and checked on the Z’s progress. The engine was ceased up but they finally broke it loose. They were very impressed by the engine block. The mechanic seems to think that it is missing a small tube that runs the length of the block. I don’t remember seeing it. I will attach a pic and please let me know if you know if you see anything missing from the block, he seems to think it should be running along the right side of the block in the last picture. It’s a 280 engine so he may be getting confused with a 240 engine.

 

So it sounds like the mechanic was was right or partially right.  If you look even more closely at the head it looks like it's been shaved, the combustion chambers aren't round.  It might not be a typical "L28" head.  Maybe an E88,which was a popular head for modifying, with a cam swap to a later self-oiling cam.  The cam towers might already be blocked off if it's been running after it was rebuilt.  

Look at the bottom edge of the head right about where I circled in the picture below and you should see a letter and two numbers cast in to the head.  E88 or N42 are most likely.

Forgot to ask also, does it have flat tops or dished pistons?  It "should" have dished if it's a US market 280Z engine.  Take a picture of the top of the block if you can.

If it's built for racing you might not be able to get much out of it on pump gas.  Might want to have it reset for street driving.

Edited March 25, 20196 yr by Zed Head

The mechanic was going to order some new arches that go over the cam because he doesn’t know how to plug the small oil holes, any suggestions? Or would it be better to just replace the arches, they already had to do a weld where they found a crack. Looks like the pistons are dished. The number I found on the head was E31. He has also had quite a bit of trouble collapsing the oil rings on the pistons. Any tricks that I can send his way. He said that the red and green need to be butted up against each other and with them butted he has not been able to collapse the ring. Thanks for your help!