RE: Tweaking TT .40 for max performance?
The method I used is a modification of the method for ABC engines that Dub Jett recommends on the Jett Enginerring site. For a TT .40, this is a rough review of the method. Get an APC 9x6 and chop an inch off both ends. Start the engine (I didn't worry about preheating the engine with a dryer, heat gun, etc.) and lean it out till its running around 20,000 and then back it off a little. Not too much or you won't get the engine nice and hot and, as the gentelman explained above, it has to get hot. Mine ran at about 19,950. I ran about three thanks through it letting it cool down almost completely between runs. I kept the mixture just rich enough to get some healthy smoke and ocassionally leaned it out a few times a tank till it was really screaming (this is when it hit hte 19,950). This seemed to have worked great for me. I have now run about a dozen or so tanks through it and it is a picture of reliability. Consistently right around 16,000 and I'm not pushing it to the limit.
For the Jett Q500 engines, Dub says to lean it out till it hits like 27,000. WOW!