i pulled the head off my 3t-c well 13t-u which i'm told is the same thing and the first thing i noticed was that the pistons looked messed up, they were flat then they have a big bump toward the front of the motor
does anyone know the reason for this, i just thought it was strange
The answer will be in the cylinder head. The bump would be there for 1) getting the comp ratio up 2) air/fuel swirl would have had a say in the design 3) the shape of the combustion chamber; the bump will need to clear the quench deck(description?) of the cylinder head - in this case, the combustion chamber is very likely asymmetric.