I bought some burrs from Enco Tools.... they have worked well on my 6 cylinder head porting
1/4 inch diameter shaft for my air grinder , various shapes. single or double cut design worked for me to rough out the shape.
I had some stones on hand to smooth out the cuts.
With porting , remember : " less is more" when you do not have a flow bench or the related knowledge on porting
Dont worry how old you are... it is the mileage on your body that adds up.