If the intake port walls are too thin near the push rod reliefs,is there enough clearance near the push rods on the outside to add some material or do you have to fill in the inside of the port and smooth it out?

 

It really depends, But you will kinda have to do both,

To gain max port width there, Here is what you do,

First, mock the motor up, then measure what clearance you have between the pushrod and the outside of the port. Then once you have that, weld more material than you need there so everything is straight when you mill the pushrod clearance, most likely if the pushrod wall is that thin, the weld will come through on the inside of the port and will have to be smoothed out. Now, I try to keep a min of .080 in those areas but, that can be pushed a bit.

-Nick