Thanks Eric, I'm an old school car guy, so Yes, I did tighten the head screws in an X pattern, I didn't take the carb apart, just off, I used traditional redish brown Form-a-gasket #2. It sat over a week because we had some rain, and then I was just too busy to take it out and I tried re-tuning it. I saw the notch on the sleeve, but not the pin on the crank case, so I'll have to check that when I tear it back down. I didn't use a gasket on the exhaust but I made sure the opening was sealed up. It was already running a little sluggish and hot ever since I replaced the clutch spring with the Hot Bodies one that my LHS told me should work when I asked for the Traxxas one 'cause he didn't stock just the spring, only the slice, and he was out of that, which was one reason I thought maybe it was the sealing because it always ran either a little too hot (about 290-310) or too rich. I'll get some of that green slime, I ordered the 2 needle carb from Mark since the Japan engine had the single needle, I got the roll of gasket material and the Permatex copper high temp gasket maker from Pep-Boys as well as the single speed tranny, different sized clutch bells, and HPI traxxas replacement clutch springs....I'll try it again when all the new stuff comes in...been trying to tune it in 95-100 degree and humid weather also...Thanks again.