Late last week I finally finished drilling out one side of the PC800 carbs for a fuel injector bung. Let me tell you, drilling on an expensive (and rare) set of carbs is nerve-wracking! The result turned out pretty well. It’s at a decent angle to hit the valves with fuel and is in a good place where it won’t come into contact with the engine. I’m a little concerned that I might have to trim the rubber carb boot insulators to make it fit but I will come to that hurdle in due time.
This is how the injector will sit in the carbs. I had to cut a heck of a lot of metal out of the way. The next step is to drill out the other side (this is about 2/3 done now. I go slow intentionally to not screw anything up) and then figure out how I’m getting fuel to the injectors and holding the fuel rails or hoses on. I would like to do it with hoses and not have to bother with solid rails. Later this week I will take an injector with me to one of the local auto parts stores to see if they have any clever ideas or products.
The injector bung, for those who were wondering, will be held in place with JB-Weld. People who manufacture injector bungs recommend using JB-Weld. The excess aluminum of the bung sticking into the middle of the throttle body will be cut away. I probably will do it with a small grinding wheel, Dremel tool, and LOTS of patience. Don’t want to make a mistake and destroy the butterfly valve or something else important.
The parts I ordered from DIY Auto Tune came in this morning. They are waiting for me at my office. This project will shortly kick into high gear. I’m aiming to have it up and running on my PC800 by the middle of June if not sooner. Still to do is installing the fuel pump in the gas tank, install the secondary injectors in the air box, cap off the extra holes in the carbs, install relevant sensors in relevant positions, install the O2 sensor bung in the exhaust system, and wire everything up. This is all getting very exciting!
NOTE: The aluminum injector bung will not be sticking out into the air stream like it is in these photos. I will cut it down to be smooth with the inner wall of the carbs. Thanks Jerry for pointing out that I forgot to mention this important point! 🙂