Going from 12% underdriven to 1 to 1. What to do on carb jetting
12-27-2022 | 02:16 PM
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Going from 12% underdriven to 1 to 1. What to do on carb jetting
Hey guys. I have.a 500ci bbc with an 8/71 blower. Want to go from 12% underdriven to 1 to 1. What should I do with the jetting when I make the pulley change? Thanks in advance for any info. It’s in a 48 Anglia street car
12-27-2022 | 09:23 PM
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I was hoping there was a golden rule like more boost equals x quantity of more fuel lol. Tell me about the AFR meter. Is that a better way to tune compared to reading egt’s? Thanks for any info
12-29-2022 | 08:11 AM
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From: St. Pete Beach, FL
12-29-2022 | 08:30 AM
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From: Cape Coral FL
If your initial jetting is close, it shouldn't change much by adding a little boost as long as your fuel system all of the way to the needles/seats is up to the task. You will have to install some O2 sensors to know for sure.
As far as timing, the last 2 blower boat engines that I did, I used the Daytona ignitions at 35 deg timing and I pulled 1 degree of timing per # of boost starting at 4500rpm. It worked well in the boats, but may not be necessary in a car.
As far as timing, the last 2 blower boat engines that I did, I used the Daytona ignitions at 35 deg timing and I pulled 1 degree of timing per # of boost starting at 4500rpm. It worked well in the boats, but may not be necessary in a car.
12-29-2022 | 12:31 PM
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If your initial jetting is close, it shouldn't change much by adding a little boost as long as your fuel system all of the way to the needles/seats is up to the task. You will have to install some O2 sensors to know for sure.
As far as timing, the last 2 blower boat engines that I did, I used the Daytona ignitions at 35 deg timing and I pulled 1 degree of timing per # of boost starting at 4500rpm. It worked well in the boats, but may not be necessary in a car.
As far as timing, the last 2 blower boat engines that I did, I used the Daytona ignitions at 35 deg timing and I pulled 1 degree of timing per # of boost starting at 4500rpm. It worked well in the boats, but may not be necessary in a car.
01-20-2023 | 04:56 PM
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If your initial jetting is close, it shouldn't change much by adding a little boost as long as your fuel system all of the way to the needles/seats is up to the task. You will have to install some O2 sensors to know for sure.
As far as timing, the last 2 blower boat engines that I did, I used the Daytona ignitions at 35 deg timing and I pulled 1 degree of timing per # of boost starting at 4500rpm. It worked well in the boats, but may not be necessary in a car.
As far as timing, the last 2 blower boat engines that I did, I used the Daytona ignitions at 35 deg timing and I pulled 1 degree of timing per # of boost starting at 4500rpm. It worked well in the boats, but may not be necessary in a car.
