when the turbine housing glows red, she's real lean- or you've been working it hard for extended periods of time - or both. it sounds like you've got a few things going on there that should be looked at. you need to 'baseline' you're tune up and go from there. Starting with putting a non-turbo HEI distributor and set the timing. i curve the dist so all the advance in at 3000, i set total timing to 29 - 31 degrees-depending on what gas and boost you run, but 30 is a good start (at 3000 rpm) with the vac advance OFF. hook up the vac adv and set the idle.
if it still runs like a dog then go through the carb. like i'd mentioned before, i got more power from an earlier pre-smog Qjet (68 - 72ish), BUT-the oem carb had better idle quality and was smoother in general, just not as fast.