It couldn't hurt to check the chain stretch but with Mobil 1 their should be very little to none of it. What about your air and fuel filters? I was also told that the rotor's and distributer caps should be changed every 60k.

Also maybe you are just getting used to the power. Maybe if you time and average a few 0-60 runs you will get a better idea of where you are.

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2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200