I did not watch the u tube except the first few seconds to see where he was going with it----------AND, I need to comment here as anyone could see that probably 99% of those over there were so called haters----------


Todays aluminum over head CAMSHAFT heads cannot just be resurfaced to flatten them because then you will have a camshaft bore that is out of alignment-----they are put in ovens and heated with various supports,etc that will cause them to come back to a flat state-----


And a far as exhaust manifolds to cylinder head---------------this is one of those BASIC mechanic things that has to be done right---maybe good enough doesn't work----------