RCU Forums - Tmaxx issues... Help please

Hi there. I am relatively new to the sport of nitro cars. I had a cheap chinese made nitro buggy several years back, and did not have any problems with the engine. Always started right up, rarely ever needed to be retuned, no problems whatsoever for several years. Anyways, I just got a used t-maxx 2.5 off ebay. It has a newly rebuilt engine, and seems to be in good shape. Problem is, I can't get the thing to run well. It seems to have a relatively cold plug on it (its not real bright when you light it), and takes forever to start... I have restored the needles to factory settings, and it will still take 15 to 20 minutes of nearly constant cranking with the EZ start before it starts... If it starts at all. Sometimes, it will wear out the ex start battery completely before it even starts. In order for it to start, I have to adjust the HSN very lean, like 1.5 to 2 turns out. Once it starts, I then have to take it back another 2 turns to the factory settings of around 4 turns... Once its running, it runs ok as long as i keep on the throttle. the second I let off the throttle the thing dies, and has no chance of restarting. I leaned the LSN quite a bit, but still the same thing. The idle stop screw is nearly all the way in just to allow it to idle somewhat. I thought it was running too rich, so i leaned the HSN a bit. This made it run much better at lower rpm (still hard to start thought), but was WAY too lean at high rpm (overheated very quickly). Like I said, I have had a little experience with nitros, but have never run into anything like this. Any help would be greatly appreciated. Thanks!
PS... It has a traxxas resonator pipe, and is running 20% fuel.