I agree, working and building them is rewarding. just be careful not to get too many. I sold my whole collection and kept just the savages and savage parts.. Its much less expensive to run just one truck than many different ones.
I bet they (hpi) will find it hard to believe your story but they will send you a carb. Its really a great truck so don't give up on it because of this.
Yeah
To add. It may be running lean. Also these engines could be sensitive to exhaust configurations so that thing you have connected could be messing with things.
I always had good luck with the 3.3. With traxxas fuel it's very reliable and is great on something lighter than a savage. Maybe they will put a 5.9 on a revo!
polishing/smoothing out the ports would not hurt. If done properly you will get some gains that may be hard to quantify by "seat of the pants" testing. I love that motor. Its very strong and reliable. Good luck. What are "fangs"