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.
Treating an underactive thyroid gland may improve mood. When someone develops depression, the brain usually becomes the focus of attention. But other organs can be the source of the problem. A common example is when the thyroid gland produces too little hormone â a condition known as hypothyroidism. Nearly 10 million Americans suffer from hypothyroidism. The condition is much more common in women than in men, and becomes more prevalent with age.