Build update 2

[ArdWrknTrk]

Mine's been tight for 13 years.
Use the blue gaskets and don't over torque the screws and warp the body or strip the threads

[mat in tn]

are you having internal or external leaking?

[Ifitaintbroke]

Not sure yet. Last time it was internal due to float being too high.

[mat in tn]

not to split hairs but that's not a leak but an overly rich setting.

[Ifitaintbroke]

In that case it actually was a leak. The float was so high the fuel level was above the level of the boosters. Tilt the carb back and it would just run out the boosters.

[mat in tn]

are you setting the float level using the bowl screw on the passenger side? another possibility could be the o ring on the inlet valve itself. if these set too long they get set in their ways. once disturbed ,even by making an adjustment they can crack and start to leak fuel passed the needle and seat.

[Ifitaintbroke]

I'll remember that. But the o rings are new. I usually set the float by taking the bowl off and lining the float up with the casting of the bowl. If that makes sense. I'm not good at describing things.

[mat in tn]

that may be a good start. but if we are talking about an 1850 or 3310 the next step is to remove the bowl screw and set the float level just to where the fuel is right at the bottom about to trickle out. using the preset method relies on the bouyancy of the float and no two are the same.you may just find a very high setting.

[Ifitaintbroke]

Good info. I'll try that. By just trickling out you mean out of the sight plug, right?

[mat in tn]

yes. it can get more involved with many different opinions on fine tuning yet the basic is just to the point of trickling out the screw hole. this is THE reason for this screw. in fact, they even made clear plastic threaded plugs for those who wanted to run a higher level and be able to see it without spilling fuel. but that gets into "other opinions".

[Ifitaintbroke]

Honestly, I'm thinking about trying something other than a Holley. I've been looking at Summit's house brand carbs. The one that they have appears to be based on the Autolite 4100. I've seen one on a 351w. The owner told me he'd had it for 12 years and never touched it, it always cranked and ran fine. They also have no gaskets below fuel level.

[ArdWrknTrk]

They're old Holley/Autolite designs made by Holley (or their factory)
All this crap is owned by the same big 'capital investment group '

Toploader carbs work fine, but I don't have gasket problems with Holley's.

If you want something else, try an AVS.
They're easy enough to get parts for.
I ran a 650 for a while.

[Gary Lewis]

That Summit carb has gotten good reviews from what I've seen.  Rick, a guy on here, has one and loves it.

And no gaskets below fuel level gets my vote.

[ArdWrknTrk]

I don't know that a 500 CFM carb is the best choice for a heavily built 460 stroker.

The biggest I ever seen a 4100 on from the factory was a 390

You can get a 750 AVS2 for the same money.  💡

Edit: I see their m08750vs for the same $.

[Ifitaintbroke]

Summit makes a 600, which is what Scotty told me to go with. As for them all being made by the same people, I don't doubt it. As far as cfm is concerned, I've got a 350cfm 2bbl that I'm going to put on it at some point just to see what it does.

[ArdWrknTrk]

Remember that 2V & 4V are rated at different depressions, so there's no apples to apples there.

If Scotty thinks you can get away with a 600 I have that 650 AVS somewhere back in Wilton.
If I ever get over there I'll make sure to grab it off the shelf.

[Ifitaintbroke]

Ah that is correct. I was just going to throw it on for fun. And thanks, Jim. I quite like an Edelbrock. I have an old Performer on it now. Poor thing has been welded on and was spray painted chrome at one point. Even down the venturis.

[ArdWrknTrk]

I've still got a bunch of tools and parts up in the barn, but access is difficult in winter with a 2wd dually (U-haul van or whatever)

Pretty sure I was last there to get a 600 Holley (08457-S) for George of Nick & George, down near the Big Easy.

IMHO the AVS2 is a better carb than the AFB.

[Gary Lewis]

The AVS, or AVS2, certainly is a better carb than the AFB.  You have to disassemble the Aluminum Four Barrel and either grind material off or add material to the weight in order to change when the secondaries open.  But on the Air Valve Secondary you hold a screw, loosen the lock screw, and then turn the adjustment screw a bit more clockwise for later opening or CCW for earlier opening.  Easy peasy.

[ArdWrknTrk]

You remember my accelerator pump saga when I first got that one, and was refurbing my new valve covers.