We started using one brand of thermostats and they were failing open, causing check engine lights. We switched to another brand of thermostat which then had multiple failures closed, causing overheating problems and an engine failure on the track. So, we made our own thermostat using OEM quality components so they will not fail. Rigorous development and quality testing was done to ensure a reliable product.
160F:
https://store.katechengines.com/160-...stat-p681.aspx
174F:
https://store.katechengines.com/174-...stat-p729.aspx
(no tune version)