They have slight slack, which grows over time. I wouldn't worry about it if your stock though. Many people including myself only change the chain when doing a cam swap or something along those lines, upgrade to a ls2 chain which is more durable and tighter. If your stock and you have like 120k and under dont worry about it, if you have like 150k then maybe I would change it to a ls2.
SLP Airbox | LS6 Intake w/PP TB | DMH E-Cutout & Pacesetter LT w/ ORY | 4.10's
TSP 228R 112lsa w/PRC Springs & TSP PR's | Katech CNC P/P 806 Heads| LS7 Clutch & Lifters | S11 Auto Detailing NEPA 415hp/390tq (Before Turbo)