78 cyclone 340/22c. Main jet

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Erie Canal Fabworx
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Joined: Wed Dec 09, 2020 5:50 pm
Real Name: Scott Miller

78 cyclone 340/22c. Main jet

Post by Erie Canal Fabworx »

Can someone please tell me what main is supposed to be in it. Previous owner had a 400 in it YIKES. Thanks in advance.. I'm pretty sure it's a 34vm slide carb
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400brian
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Re: 78 cyclone 340/22c. Main jet

Post by 400brian »

According to the parts book below serial number 70000 ran 370. Above ran 400.

Cyclones ran really large main jets in my opinion. Yet if they are set up right, I have seen some pull down 20mpg. Others will be like 10 mpg.

'09 Vintage Challenge Survivor, and I wasn't late for supper!
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Erie Canal Fabworx
Posts: 6
Joined: Wed Dec 09, 2020 5:50 pm
Real Name: Scott Miller

Re: 78 cyclone 340/22c. Main jet

Post by Erie Canal Fabworx »

Update, I've been playing with BIG JOHN, I'm down to a 330 from the stock 400 main jet... it's responding really well. I'm going to run it for a bit and see where we are...Still is a little rich mid range..
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