If my memory is working, the intake valve is 1.74" and the exhaust is 1.5" for the 194, 230, 250, and 292. I have a 194 head in the shop right now for rebuilding. The shop owner says do NOT put hardened seats in the head, period. This guy builds Chevy stuff almost exclusively, and does a lot of older heads. He told me that in his experience over the last 15 years with unleaded gas that guides give more problems by far than seats. He also advised me to go 3 angles on all the seats but leave the valves alone at 45. I have been doing business with this guy for over 35 years and he has never steered me wrong. I know that this flies in the face of what we read, but this is real world experience speaking, and I trust him enough to let him do my head.
best wishes,
Les
