Holley 600 Jets (318)

[73Swinger18]

I just installed a secondary metering block on my Holley 4160. I'm now waiting on a handful of jets to be delivered. I would appreciate anyone who has a Holley 600 mounted to a 318 to provide me what primary/secondary jet combination worked best for them. Holley tech support recommended 60/64 with the standard secondary spring. Thanks!

 

[AJ/FormS]

That would depend on the engine combo.
I'm guessing if the Holley folks recommended that combo, they probably asked all the pertinent questions. So then I would be foolish to contradict them.
I must say however, that those jet sizes seem a little small to me.

 

[Aaron65]

I agree with AJ. The stock primary jet on an 1850 in the 64-66 range, so if that's what you have, a 60 will be pretty lean. I once searched for metering plate/jet size comparisons once, and I believe an 1850's secondary metering plate was in the range of a 57 or something like that. I'd want to double check to be sure.

 

[AJ/FormS]

Got Headers and Duals?
Got bumped up compression?
Got a dualplane?
Got a light A-body? SBM-A's vary between about 2800 to 3600 with driver.
Got at least 3.55s?
Got a 2800TC?
Got a 223* or bigger cam?
Is you at 1000ft or less?

I'd start with 61/67s and, add 1/2size jet for each yes, round up when req'd
Eg; 6 yeses = plus threes= 64/70
Jet up/down, as required
I'd block the secondaries closed and get the front dialed in first.

But before doing anything I would ballpark the ignition.

I made this up just now, just so you know, but I think it's pretty close