[fordgasm]

When the new clutch was put in did you also install a new clutch cable and quadrant? Preferably an aftermark quadrant, the stock one will not hold up to a heavier than stock clutch. Cable stretch or quadrant problems can give you fits.

14 degress of timing usually is fine, but every car is different, if you run too much timing and experience detonation you can hear it pinging.

You don't need a cooler thermostat to run more timing, if it detonates back off the timing.