whats this?

[gilby]

Just pulled the rocker cover off my donor motor tonight and discovered it has these bits on the side of the left rockers where something has been removed. checked my other motor and it doesnt have them at all. can anyone tell me what was there, and will there be any effects from whatever was there being removed?

[enthuzed]

It's the jet valve head. Someone has removed the jet valves & put bolts in the head to block the valve holes. If you're not having any issues with it I'd suggest you leave it be.
If it's stuffed or your replacing it anyway then try and stay away from these heads - they have the propensity to crack!