a new stock chain and gears is around 100$, run 130+ springs and replace tensioner after 15k, then probably drop down to every 10 k afterwards, as the tensioners wear out much faster as the stock PM gears and chain wear at the teeth and pin joints.
70k stock chainset on a VS, swapped to 105 crow's (with yet another new tensioner) and 25k later the chain snapped and took out 8 valves, 4 pistons and a timing cover. so figure on changing out the whole timing set every two years, labor/gaskets/oem set.
or buy one dbl roller, properly machine and align it, and drive for 50+k without worry or scattering engine parts down the highway 400 miles from home and AAA only covers 100 miles of towing.
the chains dont really stretch, they just end up wearing together, but where the oem chain is subject to wear at both the pins and teeth, the dbl roller only exhibits wear at the pin joints as the teeth only touch rollers.
saving $ never really saves you $
