Just did my 1994 wagon 220,000 miles , it had 12 degrees of stretch, pulls much better now low to high rpm , smoother, ive always done 560 motors at 100 to 150k miles, there usually stretched 6-8 degrees, never done a 103, had a diesel 603 that was half broken, the link cut a hole into the valve cover like a chain saw , engine had about 180k miles, the diesel 642 last only to 150 max with 20 25 degrees stretch, 4 cylinder turbo engines 271 only good for 80-130 k miles, the 274 turbo engines need chains at about 78k miles and like to jump timing unsure why