How to create the spot face for the intake bolt and washer after you've re-drilled the intake bolt pattern. This provides a nice surface for the intake bolt to seat on and makes for a more professional conversion. I have started this process on all intakes made after Jan. 2004.




Start with about a 7/8" counterbore and cut off the head (cutting surface). Make a mandrel with a shaft the same size as the new intake bolt hole you drilled with the end threaded for the custom cutter you just cut off the original counterbore. This mandrel should be long enough to chuck up into a hand drill AFTER it is inserted in the intake flange (at least 3" long).





Angle view with the custom cutter attached to the hand made mandrel.





A view of the custom cutter ready for action. Be sure to run the drill in REVERSE since the cutter is upside down now. Go sort of slow and only as deep as you need to make a seat for the intake bolt and washer.