What size jets are you guys using in your Holley in Colorado?

[handloader90]

I've got a 4160 style Holley carburetor. It is a vacuum secondary, electric choke with 2 floats but only 1 metering block, the 1 metering block is located on the front of the carb.

I'm getting ready to rebuild it to put on another engine and need to swap the jets out while I've got it apart. It's coming off of an engine that was run at sea level and now I'm at 6,000-6,500 ft. above sea level.

Just curious what's a good baseline jet to start with or if someone might have the magic number that would be willing to share. I won't be tuning this thing with a wideband O2 or anything, at least not for awhile.

Thanks,
Nick

 

[Bent77]

Cfm?

 

[handloader90]

Cfm?

600.

 

[Bent77]

Try 62 front 65 rear

And you said meter plate so no power valve?

 

[handloader90]

Try 62 front 65 rear

And you said meter plate so no power valve?

It looks exactly like this one. It has a metering block but only one (in the front). I know the double pumpers and some of Holleys other popular carbs used two of them that's why I threw that in there.

I haven't tore it down yet but I'm not sure if it has a power valve or not...

 

[Bent77]

Try those 62s if you have them or something close. Probably be ok with that power valve until you get everything dialed in