SI Valves www.sivalves.com +1 805 582 0085 P.O. Box 941690, Simi Valley, CA, 93094, USA SI Valves www.sivalves.com +1 805 582 0085 P.O. Box 941690, Simi Valley, CA, 93094, USA In 1982 a small group of industry professionals with extensive valve train experience got together and formed SI Valves. Their objective was to build a company that directly served engine builders and had the flexibility to meet their needs in product requirements while providing true "one stop shopping" for valves and all types of valve train components. Contact Us Contact Us Latest News