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Since I am a "do it yourself in your garage" type guy, I decided to throw a page together showing how I added the fuel injector bungs to my Victor intake manifold. I made a drilling jig to make sure the holes are in a line and are positioned vertically through the intake runners. This will also hold and position the bungs when I epoxy them into the manifold. It is basically a piece of angle iron with 4 tubes painstakingly welded into it. Great care was taken to make sure they were the correct distance apart and were perpendicular to the angle iron. The real trick is to use your fuel rails slipped over the tubing to align the tubes while you tack them in place. Although these look equally spaced, they are not. The center tubes are 1/4" (or so) further apart than the end ones. (BTW nevermind the dates on the pics, I just forgot to set the camera's date.)
Two 7/16" bolts will bolt the jig to the intake face through the two existing holes in the manifold.
Once the jig is positioned, the bolts are tightened down and the jig is secure to the head. We are ready to drill some holes! While the outside diameter of the bung is greater than the 3/8" hole in the tube, I felt it was a good idea to start with a small pilot hole and enlarge it gradually up to the size required once the jig is removed.
Looking from the end, you can get an idea of where the drill bit will break through the casting. If everything goes as planned, the hole should be on the upper side of the nitrous/alky boss cast in by Edelbrock.
Top view of pilot holes. It looks kind of funny because the cast-in bosses that are on this intake are not exactly made on the same centers that the CHP fuel rail is. This pic was taken after the holes had been enlarged to 1/2". The bungs I'm using require a 7/8" hole.
Bottom view of pilot holes. I'm not sure if it takes guts or stupidity to take a drill to a perfectly good manifold.
Once the holes have been drilled all the way out to 7/8", the jig is bolted back on and the bungs are test fitted. The bungs actually sit on the top of the drill tubes to locate them vertically in the runners. I plan on smoothing off the rough remnants of the old bosses seen in these pics.
The bungs are checked with a straight edge to make sure they are all level with one another. 4 old injectors are fitted in the fuel rail and inserted without an o-ring into the bungs to stabilize them while the epoxy dries.
All 8 bungs are epoxied in with JB Weld. That stuff is awesome.
The bungs are trimmed and blended to the inside of the port. This might be a good time to say that it would be a good idea to trim them a bit BEFORE epoxying them in. I didn't and it took a long time and quite a few sanding rolls to sand them down flush.
As mounted on the intake. I made some aluminum straps that retain the rails and bolt on through the intake manifold bolts.
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