I 'm having trouble understanding your question. I have a 79 with a quadrajet and I'm guessing that is what you are talking about. The secondaries are controlled by vacuum. At idle and then raising rpm's to check if secondaries are opening may not be an accurate way to tell if secondaries are opening. I have a q-jet that was built by Sean Murphy, and when you are driving and give it full throttle, when the big secondaries open up you know it. You can feel and hear it. Even on a stock L-48 like I had, you know. If your secondaries aren't opening up, I suggest a carb rebuild and make sure you have no vacuum leaks. I've rebuilt stock q-jets and they are easy to rebuild. I wanted a tricked out q-jet so that is why I bought a SMI q-jet. Once again, check vacuum as there can be plenty of places for a leak on a corvette and then rebuild carb if needed.
Joel Adams
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