I have an older HF version, but still the cheaper of the two they offered at the time.
IIRC, the probe isn't small enough to go through a spark plug hole. However, I really like using it to make sure my intake runners are aligned with the cylinder head ports when installing an intake.
2021 Challenger 6.4L Scat Pack 1320 100% stock: 1.680, 11.894 at 113.75 (DA 175 ft) weight reduction, wheels, tires, Hellcat air box: 1.661, 11.686 at 115.97 (DA 710 ft)
1973 Challenger 452 ci street/strip [2008] pump gas, DOT radials: 1.454, 10.523 at 126.44 (DA 514 ft)
