Quickfuel Marine 850 Carb
#1
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Joined: Feb 2021
Posts: 77
Likes: 1
Hello,
I know there are many variables regarding the carb setup, I have a 540 with flat top pistons 305 AFR heads nice setup but need a little help with the carb. I have seen some posts claiming they did nothing to the carb others say its just to lean at wide open throttle. Should I leave the setup or change it prior to running it. Any suggestions are welcomed.
I know there are many variables regarding the carb setup, I have a 540 with flat top pistons 305 AFR heads nice setup but need a little help with the carb. I have seen some posts claiming they did nothing to the carb others say its just to lean at wide open throttle. Should I leave the setup or change it prior to running it. Any suggestions are welcomed.
#5
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Joined: Jul 2010
Posts: 524
Likes: 54
From: Windsor, NC
Don't make the mistake I made. I rebuilt one of my motors and dynod it with the original carbs that came on it and then I dynod it with a holley xp 950 I had bought earlier in the year (brand new). The motor picked up 20 hp so I ordered a 2nd holley xp 950. I put the 950 I dynod on the motor in the boat and put the new 950 on the motor I just rebuilt. It ran fine and seemed normal until I did a full throttle run and the end of the season and I burnt a piston. When I rebuilt the motor (the 2nd time) and we dynod it that new carb was extremely low on fuel. We had to do a lot of work to get the AFR right on the dyno. I guess my point is that 2 of the same carbs can be completely different so either dyno it or get some AFR guages.
#6
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Joined: Jan 2007
Posts: 2,076
Likes: 1,195
From: Murrayville Georgia
I will say this in regards to every QF carb I have run on cars, every single one was pig rich at idle. some so bad you could not be near them. all needed lots of air bleed and idle jet changes to clean them up to run decent.
#8
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Joined: Aug 2019
Posts: 1,224
Likes: 415
From: BC





