As seen on
Sign Up to Get
10% Off Your Next Order!
+ 500 FREQUENT BUYER POINTS
Be among the first to receive Weekly Specials & OPGI News.
10% off restoration parts only. 500 Frequent Buyer Points added after promotional order ships. See welcome email for full details.
Sign up for texts from OPGI, and get all our best offers and more!
By subscribing to OPGI text messaging at 80205, you agree to receive recurring autodialed marketing text msgs (e.g. cart reminders) to the mobile number used at opt-in. Consent is not a condition of purchase. Msg frequency may vary. Msg & data rates may apply. Reply HELP for help and STOP to cancel. See Terms and Conditions & Privacy Policy.
No matter the condition of your 1968 Grand Prix, OPGI offers seventeen Proportion Valve related parts to boost performance and get your 1968 Grand Prix back on the road. Choose from trusted brands like CPP, RESTOPARTS and Wilwood, with prices ranging from $5.99 to $119.99, all backed by our Price Match Guarantee. With OPGI’s 60-day return policy and thousands of verified reviews, you can shop confidently for your 1968 Grand Prix restoration. Enjoy fast shipping directly to your home, or visit our Southern California Showroom & Warehouse to see our Proportion Valve related parts in person.
Find parts that fit your vehicle