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 many symptoms, including: 1  A lump or swelling in your neck. 2  Pain in your neck and sometimes in your ears. 3  Difficulty swallowing. 4  Difficulty breathing or constant wheezing. 5  Hoarseness that is not related to a cold. 6  A cough that continues and is not related to a cold.