Finally took it for a drive!!!

...

 

I don't see any numbers on the blades...

 

Post a picture of the carb.

 

No when you have Six vehicles on the road and 5 of them run holleys you tend to accumulate a few.Plus i like to experiment when i go to the track with my truck i bring 650,700,750 and 850 double pumpers and try them all.Plus i'm a nice guy if anybody needs pars or wants to try a carb i'm the man to see.
Had three edelbrock carbs though had to beg and plead to give two of those away the third got smashed to bits by a big hammer.

 

Well you know what i love about this forum is opinions.Everybody sees things in a different way,but thats ok,usually problems are solved by different ways of thinking.

Anyway,I tried to mess around with pump cams and i always ended up right back where i started with the stock setup.I talked to Holley reps at trade shows and they said only to change cams at a last resort if you are unable to tune out stumbles and such.So i don't mess with them if i don't have to.

12 Holleys yes all good no.I also have boxes of parts too (never have enough spare parts) I have a different guy every week in the summer time asking me to look at their carbs and other guys just buy new ones and give me their old stuff.Sometimes i score a good carb other times i get a good parts carb.

 

:Handshake

 

Okay. This is coming from an EFI guy - because I wanted the computer to "change the jets and pumps automatically" - or close anyway - so I don't spend all my time at the track chasing the correct combo for that night's baraometric pressure, density, temp, timing, etc., etc., etc.). I'd rather be spending my time signing pornographs instead of changing out jets (and reading the plugs after every run).

Now that I've informed you that I'm smarter than everyone else (and that I'm a lazy-azz), on to my question. Having hung out at the track with my buddies who do have carbs, they all say (when referring to jets), "Go Squared" - meaning using the same size front/back.

Anyone else here subscribe to the "Squared" theory when it comes to track setup?

Just curious.

...and Congrats, again Scott!

 

As a matter of fact....

​

 

aahhh the ...thinking cap...
thinking next morning you did something stupid...(have read about people doing things like that)

...RFF...

 

You might call up holley (if anyone is still working there) and see what the factory jet sizes are. In theory you should never have to change jet sizes, because the airflow through the venturi is going to produce a vacuum signal which draws fuel out of the bowl and blah blah blah. This metered amount of fuel is directly proportional to the air that is flowing through the carb and subsequent vacuum signal. Now, I now this doesn't always work, because baro pressure screws with it, but unless your carb is either waaaay too big or waaaaaay too small, factory setting are generally pretty much so spot on. Some people will chase a power valves, transition circuit, or squirter problem with jets and get so screwed up that the engine won't hardly even run.

Also, the Air Bleeds play a huge roll in part throttle and idle running. If these were screwed around with too much it could cause a lot of the lean issues and stumble. Getting the air bleeds, transition slot, and a/f screw properly set up can be a huge pain the ass. There are a lot of knobs to turn there. Normally this isn't a problem, but an inexperienced tuner can get really lost really quick.

When you start making WOT passes, keeping the fuel bowls full is incredibly important. The needle and seat can some times be too restrictive and you might need to step up on seat size (not easily seen at all), or you might not have enough pump causing the fuel bowls to run low (easily seen with a FP gauge). At which point, you're only sucking fuel vapors into the engine. This is just something to think about. Without knowing what the floats are doing, a lot of people will just step up on the jets, which band aids the problem, but makes the engine run way to fat at lower RPMs.

Having a vacuum gauge, and a fuel pressure gauge (that you can see from inside the car!) along with a tuning book will allow you to get this thing running like a champ in no time!!

Anyway, just my friendly carb tuning advice.

 

You can go to the Holley carb website and they have a PDF file with all the stock parts in each carb.
Shows the stock jet sizes, PV, etc so on...

 

I have looked at Holley charts, but not knowing exactly which carb I have leads to more questions because they have 4776, 4776-1, 4776-2, ...4776-7.

Now, Can I do this...

Primary metering block has 47764 and use the recommended primary jet for the 4776-4 (#66) and secondary is 4776-2 (#76)?

Otherwise, the paired jets range from 69/71, 66/76, and 66/73, depending on which 4776-X I have.

Of course, I could randomly choose and be closer to stock than I am now, right, and not be making a HUGE change.

 

68 front 72 rear

 

This sounds good to me. I am forgetful and curious as to what I have, time to check mine out