Ignorant newbie needs help regarding head studs

What about using alumaloy sticks has a lower melting point than aluminum and is stronger about 2600 psi breaking strength, just fill the hole with alumaloy drill it out and tap it at 8mm

Ok so heres my delima now i have a new engine/crank case from my uncle he said it was for 66 cc it had a piston and head but no cylinder body so i used mine from old engine got it put back together with the parts from my first engine the only thing was when assembled my piston from my 66/80 cc Chinese motor was hitting the head but yet when i use the piston that he gave me with the case it comes up just short of TDC yes the is a difference in pistons so i had checked my plug got nice bright blue spark cleaned the air filter have gas in the float bowl have compression but wont fire but does turn over and try to fire anyways so back to TDC is it possible that the engine case i got was a 48 cc engine not a 66cc? If its a 48cc engine could i take crank out of 66cc and would it fit in the 48cc case? I dont really see a difference in the size of the case between 48cc and 66cc