Thread: Holley 650 Jet size?

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I have a holley 650 spreadbore list # 7002-1 that has most likely (definately) been modified at some point by a previous owner. His setup was a 383 sbc, I am planning on putting it on a bone-stock '71 440. Can anyone tell me the factory jet sizes for this model? I am fairly "holley-ignorant", I have always been a quadrajet type. But I needed a carb, and the price was right. I have done some research on holley tuning, but I would like to return this one to it's factory settings. That should at least give me a good place to start.
Thanks!!

I can give you a part number
Primary is 122-582
Secondary Jet or plate is 134-21(plate number)=jet number122-75
Not sure if this helps but the holley bible didn't break it down too well

Thanks Reborn, I think that will help.

If you're curious about the 3 number jet sizes, I'll try and help.
This is a direct quote from Mike Urich's Holley handbook. "In 1975 Holley developed a close-limit series of main jets in the standard size range of 30 to 74. This series was developed so flow could be more closely tailored to fit within emission requirements. These jets use the first two numbers to indicate flow range, such as 65 or 66, and a third number to indicate whether the jet flows toward the lean side (651) in the middle (652) , or rich (653)."
I personally think that 582"s on the primary side might be a little lean for your application.

My guess would be 66-68 in the front and 74-76 in the rear. Keep in mind that the primary circuit has a power valve which richens the mixture 6-8 sizes when vacuum drops( the accelerator is applied).
The way to tune the carb is by trial and error. SO when crusing on the hwy and you want to increase speed slightly, if the motor seems to stumble and then take off( I am not talking full throttle), you need to richen the mixture, (bigger jets). Go up by two sizes till you got that right. Then replace the rear jets 6-8 sizes bigger than the front ones. All this needs to be done with the floats set the right height and the timing correct first.

Thanks, That gives me a pretty good place to start.