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AcampoDave · 12-25-2022, 05:17 PM

Today the stock truck got it's turn with the o2 sensor. It has a stock 283 except for an HEI, dual exhaust and an ME Wagner PCV valve in the draft tube port. The old Rochester 2 jet dosen't have its choke connected, but after I got things warmed up, the first thing that struck me was how even the mix is at idle with the stock cam. It did vary slightly but hovered closely around 11.6. I brought that to 12.4 before it lugged a bit then I hit the road.

I was pleasantly surprised to see the numbers. It holds low 16's on the cruise and low to mid 12's when you gas it hard. It was easy to see the responsiveness of the little carb with changes in acceleration immediately having an effect on the AFR. The whole stock set-up gave such ideal readings that there really is no room for me to improve it. It's quite a testament to the accuracy of those early small block Chevy designers when you see it confirmed by technology that they could only imagine.

12-25-2022, 05:17 PM	#40
AcampoDave Registered User Join Date: Feb 2013 Location: central California Posts: 2,798	Re: Bluetooth O2 sensor and a carb Today the stock truck got it's turn with the o2 sensor. It has a stock 283 except for an HEI, dual exhaust and an ME Wagner PCV valve in the draft tube port. The old Rochester 2 jet dosen't have its choke connected, but after I got things warmed up, the first thing that struck me was how even the mix is at idle with the stock cam. It did vary slightly but hovered closely around 11.6. I brought that to 12.4 before it lugged a bit then I hit the road. I was pleasantly surprised to see the numbers. It holds low 16's on the cruise and low to mid 12's when you gas it hard. It was easy to see the responsiveness of the little carb with changes in acceleration immediately having an effect on the AFR. The whole stock set-up gave such ideal readings that there really is no room for me to improve it. It's quite a testament to the accuracy of those early small block Chevy designers when you see it confirmed by technology that they could only imagine. Last edited by AcampoDave; 12-26-2022 at 02:13 AM.