Here's a few pics, of my latest Groove job. This, on a 1989 Chevy van 305 V8 auto trans, TBI throttle body. This is for Sam King, who, also bought his Personal License Kit recently.
Welcome to Gadgetman Land, Sam!!
I did the standard epoxy fill work. First, lightly roughen all aluminum metal the eoxy will touch. Then adding "forms" that won't stick to epoxy, to hold the epoxy in place. Mylar tobacco pouch plastic, and thin cardboard wrapped in clear box tape made the forms. Filling in the idle air channel up to, and including the center divider between the bores.
This adds missing material to be able to cut full width Grooves, and allows a restriction to Idle Air Control (IAC) air flow. The T-shaped channel cut into the center epoxy puts that air over the throttle shaft, and away from interfering w/ the Groove's waveform. It might be necessary, Sam, to adjust the throttle stop screw to change idle RPM's.
I used a palm sander to make quick work of leveling the over-filled JBQuick.. Then cut the IAC channel in the epoxy with a small burr bit. A 1/8" drill bit in the Dremel would have worked, too. The Grooves were done w/ a Large bit. No danger of bit breakthrough anywhere.
This used TBI arrived from a salvage yard in amazingly good condition, as if it had maybe 30 or 40K miles on it, it cleaned up in a few minutes w/ carb. cleaner. The IAC valve was removed and cleaned separately, then reinstalled.
I thought this TBI turned out really well. I will ask Sam King to give reports on results, including fuel economy..
Tracy G.