I would suspect something mechanical ..
I would suspect some bad gasket, either headgasket, the front or rear crank gaskets, or the valve seals.
Do a compression test, if you have low compression it could be the piston rings causing the oil to disappear.
My ABY engine that I use HARD never uses any oil. (after my rebuild)
5000km and it hadn't lost anything (that I could see of the stick anyway)
Have someone follow you, floor it, then let go when you reach 5500 rpm, if it smokes then, the piston rings needs replacing.
Also have someone follow you just to see if it smokes all the time, or when cold and starting up.
I would suspect some bad gasket, either headgasket, the front or rear crank gaskets, or the valve seals.
Do a compression test, if you have low compression it could be the piston rings causing the oil to disappear.
My ABY engine that I use HARD never uses any oil. (after my rebuild)
5000km and it hadn't lost anything (that I could see of the stick anyway)
Have someone follow you, floor it, then let go when you reach 5500 rpm, if it smokes then, the piston rings needs replacing.
Also have someone follow you just to see if it smokes all the time, or when cold and starting up.

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