Can the TDC pin be off by 90 Degrees?

[Tablemaker]

Ever since I got my 31 A from my father, it has been “Running” without the exhaust/intake manifolds flush minted to the block. In other words, the engine was been running without a flush seal on the third and fourth cylinders.

After installing a brand new pair of intake/exhaust manifolds, with copper gaskets, I now have backfire during acceleration and deceleration.

I suspected the car needed to be timed. I’ve timed the engine without relief. I now suspect that the timing gear could be off by approximately 90degrees.

I followed some advice to identify TDC for cylinder 1 (by taking off all spark plugs and watching the four cylinders rise and fall)

What I’ve found, is that the timing pin more closely aligned to TDC for cylinder 2. *AND*, if I set the timing according to when cylinder 1 is physically at TDC WILL CAUSE massive backfire.

I’m at a loss in how the engine even runs using the timing pin (since #1 cylinder in already at the bottom of the stroke) and why I cannot even get the engine running when I use what I know to be TDC for #1 according physical inspection.

Can anyone help me get my fathers car running the way it should?

Many thanks,