I have seen exhaust ports brazed and filled on the bottom when raising them for SS etc.
The intake side could be epoxied, but exhaust is brazed.



1996 Ram 1500 Sport
1968 road runner
1952 Sears Allstate licensed, pump gas, Hemi 5.98 @ 115.73 1.33 60 ft. The best is yet to come. Painless Performance / Street RODDER magazine Top 100 for 2019