Not really the same but throwing my 2 cents in.
I have 516 closed chambers with hardened seats but only have the 1.74 ex valves. Been on the engine for over 20 years, no problems.


67 Dart GT Convertible 273
68 Barracuda 383
68 Roadrunner 383 4spd
1 '01 Ram 2500 4x4 diesel
2 '02 Rams 1500 4x4's 4.7s
3 '03 Rams 2 1500's 4x4 and 1 2500 hemi 4x4
Oh, and a 03 Grand Cherokee and an '00 durango smile