Calling Holley Carb gurus

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Slantsix64

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I’m going to install a 600 cfm Holley on my mild 318 carb I wanna know if I should already order different jets and power valves right off the bat for my engine the carb specs are stock 600 cfm Holley

power valve 6.5
primary pump nozzle 31
primary jet 66

my engine is a
318 Magnum,
264 duration .457 lift
rpm air gap intake
summit tube headers
9:1

I know I’m jumping the gun before installing it just wanted to hear your experiences thanks in advance!!
 
Run it as it is. Tune it to get a baseline and make changes from there if necessary.
 
Agreed with above. Get it to idle and set your timing and floats first. If it runs rich initially, that's okay. Rich is safe. It's better to chase a lean mixture.

Take it out for a spin and lean on it. Preferably on a road with a wide shoulder or a nearby parking lot so you can stop and read your plugs.

I can sit here and tell you what jets, PV, N&S, etc...I "think" you can use. But the only way to know for 100% sure is to read your plugs.

The other method if you really want to dial in the AFR is to get a dual bank wideband that can data log. That's what I have and I love it. But that may be overboard for your application.

Good luck!
 
auto or 4 spd?
weight?
gearing?
all matter on the tune
 
Doesn't the carb have a metering plate secondary?
 
Well you have plenty of gear for that carb. I assume it's vacuum secd. Be nice to know the list number to see what the secondary plate has for jetting. Depending on how ''mild'' it is and what intake you have, you may be able to up the PV some and drop the squirter down a little. As far as the primary jet, it's fine to start with in a 600.
 
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