Purchased a none running 2005 RX8 with known engine compression problems. Rebuilt engine with a new engine rebuild kit. Original cat was melted down. Removed muffler completely. Removed cat, resonator assembly, cleaned as necessary for initial start up only operation. Engine is hesitant to start, will rev's very reluctantly to three thousand rpms. 5 minutes of running and cat / resonator assembly red hot. Unobstructed exhaust. Resembles an engine with 20'+ retarded ignition timing. Reluctor wheel installed correctly with white tab facing front of engine. Looking for suggestions Thanks

 

Likely a botched rebuild, since it sounds like you are basically dumping the air and fuel into the exhaust, where it's igniting.

The rebuild kit only includes the little pieces. Did you also replace or repair the big pieces that were out of spec? Irons, rotors, e-shaft, housings...