Replacing timing chain

Id run a tensioner if your replacing a silent type chain as pictured
IMHO I would not add a tensioner. Or buy a chain that is designed for a tensioner.

I have had 2 timming chains go bad in a couple of other brand engines. Both times the tensioner falling apart was the cause. On one a piece of tentioner got between the chain and the gear and snapped the chain.

"The parts you don't add, don't cause you no trouble" my dad's favorite saying!