Pig rich mixture at idle 2 x 4 Gen 2 hemi

[Dragon Slayer]

Can you see liquid fuel in/on carburetor? Venturi not down tight or gasket leaking, top gasket torn? The fact your getting fuel in the oil certainly is a rich, or mis firing condition. What dual point did you use? Ray should tell you what cam is in it. Hemi either had the early non emission 8.5deg at distributor (total mech 17 at crank) or the 15 degree which provided 30deg mech at crank. I am not familiar with Eddy AVS, but do they already have an air bypass? The Orig carter AVS had the air bypass built in. Hole was above throttle blades in bore and bled to the base, and via machined outlet into the primary under the blades. Of course if they do, then it doesn't make sense you are so rich without a fuel leak.
Getting a good seal on a hemi manifold is important, many a vacuum leak at the intake to head and block.

 

[Beekeeper]

thanks Bob,
would it a crazy idea to run the PCV to both
carbs?

 

[Beekeeper]

Dragon,
I had discussed 32 degrees total advance on the distributor with Ray at the time of him building and curving it for me. I can see any fuel leaking outside the carbs anywhere but
when i pulled the carbs last night there was a lot of fuel pooled on top of all the closed valves.

 

[Hemirunner]

Are those cold plugs fuel fouled? Did you lower the fuel pressure? I’m not sure what steps you’re taking to diagnose, but drilling blades would be a last resort. I ran that same intake with twin AVS carbs on numerous combos with great success and have yet to drill. As alluded to, ignore the wideband, they rarely work at idle unless there’s mufflers in the system or a full length exhaust.

 

[AR67GTX]

Have you checked your float levels? I don’t know about Carter’s so much, but seems Holley float levels need to be lowered a little from spec with current, volatile fuels to prevent percolation and flooding when warm. If using race fuels may not be a problem but would check they aren’t too high. If you covered this earlier already - my oversight.

 

[Beekeeper]

Hemirunner,
I have not lowered fuel pressure yet i’m waiting on a regulator to arrive. I did get the pressure gauge installed a couple days ago to check it 5.5-6 I will get it down to 4.5-5. I have the floats at 7/16” and 15/16” drop i’ve read a few post that indicate that 7/16” may be too high although
thats the recommended setting from edelbrock what’s the opinion on that? yes the cold plugs are fuel fouled.

 

[RemCharger]

This all seems like regular stuff in the Hemi world. Part of the Hemi head DNA lol

 

[Hemirunner]

Hemirunner,
I have not lowered fuel pressure yet i’m waiting on a regulator to arrive. I did get the pressure gauge installed a couple days ago to check it 5.5-6 I will get it down to 4.5-5. I have the floats at 7/16” and 15/16” drop i’ve read a few post that indicate that 7/16” may be too high although
thats the recommended setting from edelbrock what’s the opinion on that? yes the cold plugs are fuel fouled.

I figured as much. Get the hotter plugs in and the fuel pressure down below 5. I’ve never had trouble with the factory float settings but a lot of that depends on the how the needle and seat closes. You can play with those settings easily. Get the plugs, timing and fuel pressure right first. Initial timing is for starting purposes. Timing at idle will always depend on the combo and what it likes. With lowish compression, a performance cam, and that huge chamber, it’ll love all you can give it at idle.

 

[RJRENTON]

thanks Bob,
would it a crazy idea to run the PCV to both
carbs?

Personally, .... no. That way you would have reasonably equal dilution air going to both carb primary bores. Years ago, GM/Pontiac used a simple Tee fitting in the PCV line, downstream of the PCV valve but b4 the intake manifold fittings to balance the air flow to both manifold runners.
The drilled passages in the MOPAR/Carter AVS applications located in the primary throttle bores, above the throttle plates and ending below the throttle plates, was an emission system inclusion, to help diffuse the fuel exiting the idle and idle transfer slots helping to promote smoother mixture distribution, coming off idle. (Reference: Chrysler Master Techicians Carburetor Service Highlights Book 68-2, exerpted) and as noted in #61s contribution. But these "bypass" passages are not part of the Edelbrock/Weber design as these carbs even though they are called AVS carbs, bear no real semblance to the origional AVS secondary design, other than an air valve blade above the secondary booster venturi, not present in the origional design.
Just thinking out loud....
BOB RENTON

 

[Dragon Slayer]

Personally, .... no. That way you would have reasonably equal dilution air going to both carb primary bores. Years ago, GM/Pontiac used a simple Tee fitting in the PCV line, downstream of the PCV valve but b4 the intake manifold fittings to balance the air flow to both manifold runners.
The drilled passages in the MOPAR/Carter AVS applications located in the primary throttle bores, above the throttle plates and ending below the throttle plates, was an emission system inclusion, to help diffuse the fuel exiting the idle and idle transfer slots helping to promote smoother mixture distribution, coming off idle. (Reference: Chrysler Master Techicians Carburetor Service Highlights Book 68-2, exerpted) and as noted in #61s contribution. But these "bypass" passages are not part of the Edelbrock/Weber design as these carbs even though they are called AVS carbs, bear no real semblance to the origional AVS secondary design, other than an air valve blade above the secondary booster venturi, not present in the origional design.
Just thinking out loud....
BOB RENTON

No it was not an emission system inclusion. That is not what the training manual says. An air bypass bleed is an air bypass bleed. It was a new method to replace the holes in blades with the theory the air entering at right angles to the bore would promote better idle mixing and less critical blade position with the transfer slot. Certainly better mixing would help emissions. Holley still used holes in the blade.

Anyway as I stated earlier and hemi runner is stating a hotter plug, and figuring out the excess fuel. I am surprised that the edlebrocks don't handle the fuel pressure as well as the carter did, but I guess the larger needle seat and smaller float do put them at a disadvantage wrt fuel pressure. I am not sure about your cam effect on vacuum, but I would think your vacuum should be higher at idle also. Lastly on the distributor, did Ray state an initial timing for your 32 total? The 68 up street hemi had 30 out of distributor and initial was set at 0 degrees. So you still need to know how much mechanical it is adding.

 

[Beekeeper]

I have the distributor spec sheet but I’m not smart enough to read it
once I figure out the initial timing I was gonna have Ray recurve it to be 32 total I’m not sure how much the vacuum advance adds.
How does one determine if the manifold is leaking? I have torqued it several times now and there’s no evidence I can see of it sucking oil.

 

[pnora]

I have the distributor spec sheet but I’m not smart enough to read it
once I figure out the initial timing I was gonna have Ray recurve it to be 32 total I’m not sure how much the vacuum advance adds.
How does one determine if the manifold is leaking? I have torqued it several times now and there’s no evidence I can see of it sucking oil.

First of all intake leaks the bad ones are on the bottom side. So harder to diagnose. One simple test I do to see if the intake is leaking is this. As long as there are no other crankcase venting except the valve covers this should work for you. Remove all pcv and plug them. Plug all valve cover ports on one side. Start and run the engine. On the unplugged valve cover side you either will have crankcase gasses escaping or a slight vacuum. If vacuum you know the intake is leaking. I suspect the no idle below a lower RPM and high A/F, along with all you have tried to correct doing nothing could be a serious intake leak.

 

[Fran Blacker]

Unlighted propane torch, around intake. Might need to block wind from fan. No lean plugs right so who knows.

 

[INTMD8]

Maybe I missed it but have you confirmed the timing mark is correct?

Sounds like it needs more initial timing.

 

[Beekeeper]

Maybe I missed it but have you confirmed the timing mark is correct?

Sounds like it needs more initial timing.

Yes it’s a new balancer and was verified when I degreed the camshaft.

 

[Beekeeper]

Here’s a couple pics when I check the intake fit with Prussian blue.

 

[khryslerkid]

I can see any fuel leaking outside the carbs anywhere but
when i pulled the carbs last night there was a lot of fuel pooled on top of all the closed valves.

I did get the pressure gauge installed a couple days ago to check it 5.5-6 I will get it down to 4.5-5. I have the floats at 7/16” and 15/16” drop i’ve read a few post that indicate that 7/16” may be too high although
thats the recommended setting from edelbrock what’s the opinion on that? yes the cold plugs are fuel fouled.

I'd shoot for 4-5 lbs.

If you have fuel pooled like that in the heads, it's definitely a flooding condition.

What pump are you running?

 

[moparedtn]

Pardon my ignorance here, but would a 19.5:1 A/F be excessively lean?
Seems like I recall a better target being around 14:1 at idle and maybe 13:1 at full pull?

Still asking about that reported 19.5 on the O2 reading...

 

[khryslerkid]

Still asking about that reported 19.5 on the O2 reading...

Maybe post #47 will answer your question.

How ya doing Ed

 

[Fran Blacker]

Is it practical to setup a gravity fuel supply to carbs? Fuel regulators will come just after you set it up, guaranteed !