Surely the just-after-TDC is the just-before-TDC of the next piston. Two compression cycles for each rotation of the crank on a four cylinder. My Ferguson T20 tractor engine (same as the Standard engine fitted to the Vanguard and the TR2 and the Morgan +4) is in bits at the present and has two chewed sections on the starter ring opposite each other - one much worse than the other.
Only the cylinders with both valves closed will affect the stopping position so induction and exhaust are irrelevant. The compression stroke will drive a stopping the engine backwards and the power stroke which is no longer ignited will push the engine forwards because of the compressed air it contains. Under perfect conditions this should be equal on all cylinders and the engine should stop low down on the compression stroke of any one of the four cylinders - hence two chewed places on the starter ring.
However, as noted above ring wear and valve seat wear will make the compression efficiency different for each cylinder so the engine will have a preference to stop where the differential is greatest between the compression of two cylinders which fire next to each other in the sequence - so in a 1,3,4,2 engine 1/3, 3/4, 4/2 and 2/1. The well sealed piston will stop on the compression stroke and the leaky one on the power stroke.
Obviously, I want to use the unchewed bits on my starter ring, but none of this is any use to me because the pistons, rings, and sleaves are all new and the valves re-ground so the engine will probably stop in a different place and replacing the flywheel rotated by 90 degrees, probably won't help. Just bolt it back together andd hope as usual.
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