Just another 2bbl conversion thread

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Sep 26, 2009 | 06:57 PM

MotherTruckinMarine

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Just another 2bbl conversion thread

Most guys dont see the point of slapping a 2bbl carb on a factory stock intake manifold. As for me, it seems to be the ticket atleast for now. Being a new dad, I am broke and jonesing for a new project. I am also very displeased with the Carter 1bbl. Doesnt give me much on the highway at all. So, Ive got this Holley 2bbl from a mid 70's LTD that I am going to rebuild. I found a 2-1bbl adaptor that will work perfect to the tune of $12. My plan is to bore the 1bbl hole as large as possible and match the spacer to the same diameter. I will also slap on some EFI headers if I can figure out how I will do the exhaust on the cheap. I dont want to port the heads for fear of voiding my 100,000 mile warranty on the long block. BUT, I will be adding chevy 250 rockers.

The one thing I am wondering is for someone who has installed this carb on their 300. I am thinking I will have to rejet the carb but I dont know where to start. Any suggestions?

Sep 26, 2009 | 07:04 PM

Harte3

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From: Spokane, WA

Get installed and running and then see if the jets need changed one way or the other.

Sep 28, 2009 | 01:27 AM

MotherTruckinMarine

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Okay, I did some learning and found out that the carb I have has 1.08 venturi's. I was wondering what venturi size works best with the 300?

Sep 28, 2009 | 07:21 AM

Harte3

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1.08's are highly desirable and should work well.

Sep 28, 2009 | 10:58 PM

Pkupman82

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From: Muskegon, MI (home)

The 2bbl adapters do make a difference, I had one on my 84 F150 for a short while until I had the loot to get the Offy DP. You will be surprised how much it wakes these motors up, the EFI manifolds are a great I idea too.

Sep 29, 2009 | 09:39 AM

1986F150six

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From: Sheffield, AL

MotherTruckinMarine,

Go to Fordsix.com and push the tab for Technical Section. There are two excellent articles which will be of interest to you: (1.) Upgrading to a 2V carb (2.) 2V dyno comparison.