92 tracker Compression issues....

I have multiple problems to figure out and I probably won't be able to start my tracker with only 70lbs of compression on each cylinder.... I have about 150,000 miles on my tracker.... I get my compression reading when cranking the engine (fully charged battery) over with a gauge on one plug at a time. The spec say I should have 170lbs at 400 rpm. Has anyone had compression issues that went favorably without doing a major engine overhaul?

1 month later....
Ok, at factory marks on the cam and crankshaft(cylinder 4) I figured out that if i go CCW on the crank and set it almost 2 teeth before top dead center(where the piston begins it's downward decent) I get my compression back. My nieghor/mechanic is going nuts and saying this can't be and it's not right. As it turns out, it the only spot where the car will run properly.
What went wrong with my factory marks for TDC? I can only speculate after leaving a ratchet on the crankshaft and starting the car... the ratchet slammed dead into something and advanced the crank this far where I need to put it. My neighbor/mechanic say no f'n way.... I say the hell with it as this is the only option without tearing into the motor. Anyone had issues similar to mine?