engine running 220 deg consistently..

You might try burping the coolant system. You could also try some water wetter. You could wire a manual fan switch (this gained me the most cooling gains, I run between 180-195). Your u/d pulleys might not be spinning your water pump fast enough. You could try swapping those back out too.

Are you running hotter at speed or in town? How are ambient temps? My bud lives in Ypsi and said it has been 90*F and high humidity lately.

I would not worry about the pulleys for now if you are running hot at speed too (which would suggest the system is simply not rejecting heat very well).

Good luck.

Yeah, you dont need to have the fan on at all times. If it runs when the t-stat is closed, it is not doing anything.

A decent stat might help you out. A balanced unit is the way to go - both stangs have Mr. Gasket 180* units here. They are fully balanced, open fully sooner and have a bleed hole. Some parts store stats dont open till 10-15*F past their rating. While a cooler stat is not a solution, it does help and might really help if your stat is not that great (when getting on it, an unbalanced stat can take some time to open up).

With the stock stat temp rating, the low speed on/off temps are about perfect. You could lower the threshold for the high speed if you wanted to. With a 180* stat, I would lower both thresholds.

My two cents.
Good luck.