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300ex jetting
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Posted by: lumpy300

I just rebuilt my 99 300ex with a .080 11:1 wiseco piston. it already had a 400ex carb on it. just curious what jets to run with it @ 1500 ft. already has a 45 pilot with a 155 main. any info would be appreciated.

Posted by: TarheelRedRider

Open air box or closed.

Posted by: lumpy300

air lid is on with a dg exhaust, uni filter (new) and stock cam.

Posted by: TarheelRedRider

Try it where it is first with a new spark plug, Then pull the plug and see if its lean ( plug will be ashy white) or rich ( ashy dark brown ) You will want a lite tan color to be in the right air fuel ratio.