No matter the condition of your 1975 Riviera, OPGI has the Proportion Valves you need to boost performance and get you back on the road. We currently carry twelve Proportion Valves to choose from for your 1975 Riviera, and our Price Match Guaranteed prices range from as little as $8.99 up to $115.99. OPGI offers CPP plus three other trusted brands of Proportion Valves for your 1975 Riviera, to help you find quality parts you can rely on. With OPGI's 45-day return policy and thousands of customer reviews, you can shop with the utmost confidence. Enjoy parts delivered directly to your home, or visit our sunny Southern California Showroom & Warehouse to check out our Proportion Valves in person.