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Proportioning valves help regulate brake pressure in your 1970 Bonneville to maintain proper front-to-rear balance. By limiting pressure to the rear brakes during heavy braking, these components help prevent wheel lockup and improve overall braking stability. OPGI offers eighteen Proportion Valves designed for proper fit, function, and reliability. From factory-style replacement valves to adjustable options, you’ll find quality parts from trusted brands including CPP, RESTOPARTS and Wilwood to help restore balanced and predictable braking performance. Every purchase is backed by our Price Match Guarantee. Plus, with OPGI’s 60-day return policy, you can shop confidently when selecting parts for your 1970 Bonneville. Orders ship quickly, or you can visit our Southern California showroom to see select components in person.
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