<div class="bbWrapper"><blockquote data-attributes="member: 362" data-quote="elwood blues" data-source="post: 455488"
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data-content-selector="#post-455488">elwood blues said:</a>
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I'm not going to offer you an opinion on what brand name or make to buy, every carb has both positive and negative points, it's really going to come down to what you are going to do with your CJ.<br />
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I will supply you with the formula for CFM rating that you'll need;<br />
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<span style="font-size: 15px">CID x RPM / 3456 x VE% = CFM**<br />
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</span>CID= Cubic Inch Diameter<br />
RPM= Maximum Engine RPM<br />
*VE%= Volumetric Efficiency<br />
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* Most engines are capable of achieving only about 80% VE (Volumetric Efficiency). A modified street engine with ported heads, headers, intake and carburetor can achieve about 85% VE. With extensive head and valve work and a new cam an engine may reach 95% or even more. It's normally not possible to achieve VE's over 100% without some form of forced induction.<br />
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** This represents the minimum CFM required, to support a certain cubic inch engine at the maximum RPM potential of that engine. The number represented does not account for obstructions such as air filters, or inaccurate CFM ratings found on some carburetors.<br />
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<span style="font-size: 15px">360 x 5000 / 3456 x 80% = <span style="color: red">416.66</span></span><br />
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From any information I could find 5000 RPM is redline for a stock AMC 360. This is the MINIMUM CFM rating, so nothing smaller than the 416 number. That being said, most carb CFM ratings are overexagerated, my 2¢, I would say a 650CFM carb would suit you well <img src="/community/smilies/beerchug.gif" class="smilie" loading="lazy" alt=":chug:" title="Chug :chug:" data-shortname=":chug:" />
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Back when I had a carb business, used the same formula ( from the Holley Manual ) to show folks that a 750 CFM wasn't really needed on a "headered" small block. Good to see it, haven't used it in a long time. Didn't mean to snatch the thread. <img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f642.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=":)" title="Smile :)" data-smilie="1"data-shortname=":)" /></div>
