If you are paying that much $ for a car It should be inspected by a somebody that knows what they are doing or it should be the buyer responsibility. No difference in buying a house, you get it inspected because you don't know anything about it.
In the state of Ohio it legal to use a donor car to rebuild a car, when you are finished building the car it has to go to the State Highway Patrol for a new vin #
I think you have a bent exhaust valve, Doing a high RPM burnout might have floated a valve and it hit the piston ? Have you run a compression test yet.
Did you use a paper gasket with the valley pan ? You should always use a paper composite gasket with aluminum intakes.
Take a long piece of vacuum hose and put one end in your ear and go all around the intake and carbs and see if you hear a vacuum leak.
These belong to a friend of mine, not sure how old they are but they are in nice shape. He wants $1500.00 for them and it includes the solenoid and bracket, lines & linkage.
If interested PM me, Make me a offer, I will send it to him. He really wants to sell these If they don't sell I will...
I have 1 rocker arm I found while cleaning out some parts it's had the tip reground and is in nice shape $35.00 + $5.00 shipping PP friends & family or you pay the fees
Thanks