overheating GTV-6

[OGORZALEK JAY THOMAS JAMES <Jay.Ogorzalek@domain.elided>]

I'm sure this has been asked in one form or another over time, but here it
is again:
My '83 GTV-6 has this horrible need to overheat in any stop and go city
traffic. The radiator has been raughted out, water pump replaced,
thermostat is still good. What could be the problem? The car is lowered a
bit in the front end, and possibly has some hotter cams, but not S style.
Also, only one of the twin fans works, but is hot-wired to run at full
speed at the flick of a switch. Even with this on, the car boils over
horrendously. What could be causing this atrocious problem? 
Any info would be appreciative.
Thanks,

Jay Ogorzalek
'83 GTV-6
Boulder, CO

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