If you have an HEI distributor with a Tach Output you can use the Tach Output from the distributor. Due to the high voltage of the signal from the HEI you should use a tachometer filter to prevent damage to the tachometer. Coil Pack or Individual Coils (Distributorless Ignitions).
Yes, thyroid disease can affect your mood â primarily causing either anxiety or depression. Generally, the more severe the thyroid disease, the more severe the mood changes. If you have an overactive thyroid (hyperthyroidism), you may experience: 1  Unusual nervousness. 2  Restlessness. 3  Anxiety. 4  Irritability.
Thyroid cancer can cause any of the following signs or symptoms: 1  A lump in the neck, sometimes growing quickly. 2  Swelling in the neck. 3  Pain in the front of the neck, sometimes going up to the ears.  Hoarseness or other voice changes that do not go 1  away. Trouble swallowing.  Trouble 1  breathing. A constant cough that is not due to a  cold.