74 fj40 carb jetting (1 Viewer)

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Hey guys, new to this site. Thank you for wealth of knowledge. Just completed building the f 1/2 engine on this 74 fj and to my surprise this carb has much larger jets than book calls for. Apparently the main primary and secondary were installed backwards before I got it. Can anyone help me with finding correct jets for this carb? Note, all 80 or so jets that I have are too large. Thanks in advance.
 
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What elevation are you at? And is it the stock '74 carb?
I'm at about 700ft here at home, I'm heading to Colorado to drive several mountain trails as soon as I complete the carb & SOA swap I'm currently working on. It's real important to me to finish this project , I'm getting married and going on this trip for a honeymoon 😁.
 
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Apr 1, 2021
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I'm at about 700ft here at home, I'm heading to Colorado to drive several mountain trails as soon as I complete the carb & SOA swap I'm currently working on. It's real important to me to finish this project , I'm getting married and going on this trip for a honeymoon 😁.
Oh, & yes it's a 74 car to my knowledge , there is a tag with 60205 on the carb.
 
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Thats a spread of elevation if you live at 700 but are planning to take it up into the mountains. I currently live at 1000 ft and have my carb set up like Jim suggested :

120 primary
180 secondary ( or 200 if I had one)
60 & 80 slow jets
80 power valve jet

When I lived in Colorado at 8000 ft and regularly drove it higher:

114 primary
180 secondary
50 & 50 or (60) slow jets
60 power valve jet
 
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Joined
Apr 1, 2021
Messages
5
Location
Ok
Thats a spread of elevation if you live at 700 but are planning to take it up into the mountains. I currently live at 1000 ft and have my carb set up like Jim suggested :

120 primary
180 secondary ( or 200 if I had one)
60 & 80 slow jets
80 power valve jet

When I lived in Colorado at 8000 ft and regularly drove it higher:

114 primary
180 secondary
50 & 50 or (60) slow jets
60 power valve jet
Wow, thank you for your time & info. I will use your information in setting a baseline for my carb.
This cruiser was running so rich when I got it that After 5 mins of driving my clothes smelled of fuel exhaust so bad I would have to change.
 

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