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MXmaniac · 07-15-2008, 12:03 AM

Does anybody have a factory service manual that could tell me the main jet size for a 292ci with a Rochester B single barrel carburetor? The carb I just put on is off of a 230ci and made the motor real lean. So I stole the main jet out of the Rochester M(later model) that I used to have on the 292 and it made the motor too rich.

I have a 1970 service manual that calls for a .128" mainjet in the Rochester M carburetor. The jet I have out of the M is larger than .128" and made it run rich with the Rochester B carb. I ended up drilling out the smaller jet from the 230 a little to come up with something in between and it works pretty well, but I'd like to know what the factory specs call for.

Thanks,
Andrew

07-15-2008, 12:03 AM	#1
MXmaniac Registered User Join Date: Jan 2007 Location: Denton, Texas Posts: 356	292 main jet size? Does anybody have a factory service manual that could tell me the main jet size for a 292ci with a Rochester B single barrel carburetor? The carb I just put on is off of a 230ci and made the motor real lean. So I stole the main jet out of the Rochester M(later model) that I used to have on the 292 and it made the motor too rich. I have a 1970 service manual that calls for a .128" mainjet in the Rochester M carburetor. The jet I have out of the M is larger than .128" and made it run rich with the Rochester B carb. I ended up drilling out the smaller jet from the 230 a little to come up with something in between and it works pretty well, but I'd like to know what the factory specs call for. Thanks, Andrew __________________ Andrew '69 C-20(292, 4-speed) Retired Daily Driver '64 C-10(250, 3-speed) Fixerupper '97 F*rd Mustang GT(4.6L, 5-speed) Daily Driver If I only wanted two pedals I'd have bought a bicycle.