SBC 2.02 Reliefs in Combustion Chamber

[dlv4540]

Does anyone know what year they started cutting the reliefs out of the combustion chamber on the 2.02 valve heads? I know 1969 and newer had it but I am getting mixed opinions on years prior to that.

[Vortecpro]

I really never noticed the chambers cut from the factory on the 461 462 291 heads, 186 and 492 yes.

[Hotrodpaul]

I believe all SBC chevy heads with factory installed 2.02" intake valves were relieved with a cutter in the combustion chamber to reduce shrouding. This could have been as early as 1962 or 1963. On the 340292 Turbo head OTC, the cutter diameter was reduced slightly.

Paul