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O2 sensor required??

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Old Aug 15, 2023 | 03:40 PM
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Default O2 sensor required??

Hello C3 people, i have a manual 81 with sotck engine. The carb has been replaced with Holley street warrior 600 cfm. All the wires to CCC from the original qjet are unplugged.
Since the CCC as no carb info/control, I guess the O2 sensor is no required anymore... Is that right? My o2 sensor has just broken in two pieces and I will replace it by a M18 plug if the sensor is of no use.
Bonus question: How do you remove the spark plug from cyl 3.... Man these plugs are a hassle. Thanks!!
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Old Aug 15, 2023 | 03:50 PM
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Nope, you do not need the O2 sensor since you changed the carb. It was part of the CCC and worked with your old quadrajet. Did you also change the distributor? The stock computer controlled distributor will not work right either.
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Old Aug 15, 2023 | 04:04 PM
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No, i still have the original have the timing seems good to me. It's about 12deg at 1000 rpm, 24 deg at 2000 rpm and 30 deg at 3000 rpm.
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Old Aug 15, 2023 | 04:12 PM
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So you still have the original CCC system still connected for the distributor then. When I did mine I replaced the distributor too just so I could get the curve set right. Are you getting a check engine light? I am not sure how the CCC will react to using the CCC distributor but without the CCC carb. Most of us have changed both the carb and the distributor out when we got rid of the CCC system.
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Old Aug 15, 2023 | 04:20 PM
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Yes, I have the check engine light with these 2 codes : 21 (TPS-throttle position sensor) and 23 (mixture control solenoid). I believe these were info from the qjet. I was planing to change the dist but the car runs good and the advance seems ok to me....
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Old Aug 15, 2023 | 04:27 PM
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Yes those two codes are from the carb. I think you would be better off changing the distributor out too and getting one with vacuum advance on it. The stock CCC distributor does not have any vacuum advance for timing on it. The CCC distributor might work but may not be optimal for your timing curve.
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Old Aug 15, 2023 | 04:33 PM
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So you have no vacuum advance?
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Old Aug 15, 2023 | 04:53 PM
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nope
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Old Aug 15, 2023 | 05:28 PM
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Originally Posted by Bikespace
So you have no vacuum advance?
Originally Posted by by667
nope
Your timing, and current distributor, are leaving a lot of performance on the table. Email @lars for his timing and HEI papers, and get that sorted.
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