Timing Confusion After Engine Swap

[perspectiveshifting]

I've effectively completed an engine swap on a 1973 240z, and am running into what I hope to be my last roadblock in the process. Despite my best efforts, I can't get the timing anywhere near normal on it. It runs at its current setting, which clocks in at about 55 degrees advanced, but lags tremendously at higher Rpms. Attempting to lower the advance results in the engine refusing to start, and also requires shifting the spark wires to a different position on the distributor cap, as the distributors timing adjustment limitations are reached. 

 

I've gotten several different suggestions as for what could cause the issue, most prominently the possibility of the timing chain being installed incorrectly. This is a distinct possibility, as the engine was completely rebuilt but unused by a previous owner. Is this the most likely issue, or are there more common reasons for me to be experiencing this issue?

 

Thank you in advance for the assistance, and let me know if I can provide anymore context to help this question be answered. You all are awesome!

[DanielC]

I really do not think the engine would run if the spark ignition was 55 degrees BTDC.   A spark at that time would force a cranking engine backwards, and stop it.

 

You should be able to see the piston throught the number one spark plug hole.  Make sure the crank pulley and timing pointer are at TDC, when the piston is.

Once you know that. then check the camshaft is at the correct position, with the crankshaft at TDC.

[perspectiveshifting]

TDC has been confirmed via the number one spark hole, and aligns with timing mark on car. Very possible something is causing me to misread it some way I'm not aware of, but the crank pulley and timing indicator do appear to be at TDC when the piston is.

[docbainey]

If you feel your cam timing is correct, then the distributer drive is probably a tooth off.

[datzenmike]

To be clear the timing chain has zero to do with ignition timing. Most likely the oil pump distributor drive spindle is clocked wrong.

 

At TDC take the distributor out and look down at the top of the drive spindle. It should be like this...

 

[Doctor510]

TDC has been confirmed via the number one spark hole, and aligns with timing mark on car. Very possible something is causing me to misread it some way I'm not aware of, but the crank pulley and timing indicator do appear to be at TDC when the piston is.

FYI, just because the #1 piston is at TDC when you check it, so is #6.  If you pull the valve cover, you will see that #1 if the cam lobes look like Mickey Mouse ears (10/2 on a clock) you are at #1 TDC, if they are pointing down. #6 lobes will be UP.  Rotate the motor until the #1 lobes are UP, the pulley should show TDC.  Where ever the rotor in the dist is pointing, that is your #1.