if your on the #1 plug wire then your 180 degrees out, i dont know if it is even possilble to drive like that. from what is seems it sounds like its running too hot. my big block is the same way. at about 180 degrees the throttle response and low end punch is good, once it warms up completely at about 210 (with 180 thremo.) it doenst run as good. pay close attention to your water temp gauge and flush your cooling system and get a new thermostat if it is getting hot. the reason i think it too hot is because you said it runs good cool.
if its not that, i know some fuel enjected vehicles have a throttle position sensor (TPS) and if it is off, then everything is off; including fuel input, timing, etc.
Mass air flow sensors also affect the way you engine runs with your characteristics, but again i dont know if you have one...