440 six pack idle help

Here we go again some of you may say. I have read bunch of information on the web about how to tune these carbs. Here is my
Issues. I have a 70 cuda with 512 stroker from 440 source, aluminum intake, fairly lopy cam (picture of cam card attatched). The car runs great with tons of power when I drop the hammer but when I come to stop, car dies. I have tried all the tricks, vacuum test, power valve changes, new jets, 1/8 to 1/4 outboard a/f idle mix screw adjustment, checked for air leaks. Currently I installed 4.5 power valve and have the choke pull off disconnected and the outer carbs mixture screw 1/2 turned out and seems to respond the best but runs very rich during low rpm when driving. Every time I fully open the center choke flap engine will stall and die. Someone said most likely a vacuum leak but I have not been able to find it. Also when I choke off the air completely on both outer carb it will stall too.
So... I am stumped and appreciate the advise in advance.

I would test the power valve to make sure it is not ruptured or the gasket is leaking
I had a similar motor, 400 block bored to 4.375 with a 4.25 stroke crankshaft with 9.25 to 1 comp ratio with a comp Cams solid roller with 260@.050 on the intake lobes and 266 @.050 on the exhaust lobes, ground on a 108 LSA and installed 2 degrees advance so the intake lobe center was installed at 106 ATDC.
It had a low deck Eddy six pack intake with a set of OEM Holley 1970 440 6 pack carbs. with a 2.5 power valve, it would idle at 850 RPM in gear and 1000 RPM in neutral,it was a ton of fun to drive
I did have to work on the carbs to get them to do that though, 1/2 turn out from bottomed out on the outboards mixture screws and right at 1.5 turns out on the center carb. No choke plate or bar in the center carb., the accelerator pump squirter was a #35 I think, I did use a screw with a nut on it in the return slot on the center carb to start opening the outboards sooner when I went to WOT, I had to try different locations on that but I think it was around 1/3 of the way from the top at idle in that slot. I did have a custom built 10 inch converter at first and later a 8 inch T/A SS race hemi converter that worked great on the street and at the track, way better than the 10 inch street and strip converter
It will work great once you figure out what is currently wrong

What size jets are you using in centre carb.

If it idles better partially choked, you have a vacuum leak. Hand over the cab at idle to verify (choke fully open).

Any additional details on exactly what it does at idle without choke might be helpful info.

Make sure you have at least 25° ignition advance at idle.

It needs to have the timing advanced. my 2cents

Start with the mixture screws on all 3 carbs out 1 1/2 turns.Put your finger over each air bleed and adjust the screw for that air bleed in or out so that when you cover the air bleed the idle does not change. Last one I set up ended up at 1 5/8 turns on all 6 mixture screws.

#65 jets

It's hard to diagnose via the internet as we can't see or hear the operation of your set up, along with just the supplied info on hand, that being said I like to start with the basics to sometimes cover the most obvious often overlooked, you gave no mention of checking/setting fuel level in each bowl, to me this is the first operational/running step after confirming all mechanical installation procedures...


I'll mention this just for sh!ts and giggles: but I've come across 2 guys so far over the years that either daunted or unfamiliar with the set up, that have installed the center carb as delivered new from Holley, unfortunately Holley attaches and clips a hose from the PCV port to the bowl vent tube (why?), yeah the set up runs! (barely), but the PCV "vacuums" the bowl dry of fuel... it's simple problems like this that can cause some to render " complex solutions to simple problems", you/we need to know that all of the basics from installation to operational set up have been performed

Mike

And depending on whether you carbs original complete units or have been messed with or anything changed,I get more and more end carbs with center bows that have the accelerator pump passages filed with JB weld and used as end bowls.It will work "but" keep in mind the sight plug on the center bowl is 1/4" higher than the end,consequentially you have a 1/4" higher float level if you adjust float level as recommended and you are going to have problems.

[quote=Cab_Burge]I would test the power valve to make sure it is not ruptured or the gasket is leaking
I had a similar motor, 400 block bored to 4.375 with a 4.25 stroke crankshaft with 9.25 to 1 comp ratio with a comp Cams solid roller with 260@.050 on the intake lobes and 266 @.050 on the exhaust lobes, ground on a 108 LSA and installed 2 degrees advance so the intake lobe center was installed at 106 ATDC.
It had a low deck Eddy six pack intake with a set of OEM Holley 1970 440 6 pack carbs. with a 2.5 power valve, it would idle at 850 RPM in gear and 1000 RPM in neutral,it was a ton of fun to drive
I did have to work on the carbs to get them to do that though, 1/2 turn out from bottomed out on the outboards mixture screws and right at 1.5 turns out on the center carb. No choke plate or bar in the center carb., the accelerator pump squirter was a #35 I think, I did use a screw with a nut on it in the return slot on the center carb to start opening the outboards sooner when I went to WOT, I had to try different locations on that but I think it was around 1/3 of the way from the top at idle in that slot. I did have a custom built 10 inch converter at first and later a 8 inch T/A SS race hemi converter that worked great on the street and at the track, way better than the 10 inch street and strip converter
It will work great once you figure out what is currently wrong [/quote

The outer carbs screws are about 1/4 turned out and center is at 1-1/2 currently. I will try with a lower power valve at 3.5. Far as power valve or power valve bowl leaking, I did the pressure test and they are both good.

I will try advancing to 25*, I don't think I tried advancing that far but will give it a shot. Far as the air leak is concerned, most people it talked to said the same thing that there is a leak. It is difficult to tell as the outer carb does take in some air naturally ( I could be wrong on this) but as I stated earlier, when I cover up the outer carb with a rag, it sputters and eventually dies. When I open the choke plate wide open while idling, I have to have my hand over the cab in order to keep the engine running.

1 1/2 turn out for all 6 mixtures seems bit much I don't want to wash the cylinders out. I will try by turning them out another half turn and see what it does.

Sounds like a Vacuum leak or it is way to lean... Also recheck the float levels.... Are you running a low stall convertor also? That cold be an issue?

It's not too much. And thats only the starting point. You adjust further by covering the air bleeds and turning the mixture screws in or out til you can cover an air bleed and the car's idle neither speeds up or slows down.. I read this info from Larry Shephard's 6 pak book years ago, and to me it also seemed like too much. But it was the thing that turned the corner for the 1st one I ever tuned. I thought I had jetting problems, a plugged center carb metering block, I thought I had to drill open the holes in the secondaries more, and none of it helped. But opening the mixture screws on the end carbs to be close to what the center carb wanted was the key. The car has to idle on all 3 carbs, and not just just a trickle out of the end carbs, either. Your nose and your eyes will tell you if its too much. So long as your floats are adjusted properly , 1 1/2 turns out on all 3 is the place to start tuning. Before you can adjust jetting, secondary diaphram springs, etc. it has to idle, and idle cleanly. It's counterintuitive, but it worked for me. If it were me I'd put the carbs all back to stock so I'd have a baseline and start there.

Thanks Mike. I did fail to mention couple things. All 3 carbs are original 70's, the main body was slightly warped and was milled. There was a leak in the power valve bowl as it was not holding vacuum but since the milling, its holding vacuum now. The pcv port is located on the bottom. I will post a picture of the setup later this afternoon. I think I will also post a video and attach a link so all of you can better see my dilemma.
Far as the fuel level float is concerned I have messed with this many times. its currently set at half meaning basically fuel dribbling over the sight hole, if I lower the fuel level any farther, engine will not respond very well. I think I have this dialed in correctly.
One thing I was told to check was the fuel pressure. I am currently using mechanical Holley high volume 8 psi. Everything I read says use 6.5 fuel pressure regulator but does 1.5 pressure make that much difference?
Everyone I talked to says a vacuum leak somewhere.. One thing I have not triedis trying out a difference pcv valve. Could this cause too much air?

Its a manual 4 speed and it stalls when I open the choke when its warmed up. I think float level is good but I am now second guessing potentially about the fuel pressure. I posted on a response to Mike that I have a mechanical fuel pump rated at 8psi. Not sure if 1.5 psi makes a difference.

Thanks Everyone for you help so far
Here are the following things I will try based on your suggestions

1.. I will set the mixture screw on all 6 at 1.5 turn and adjust from there.
2.. I will exchange out 4.5 power valve to 3.5

3.. Different PCV valve.. perhaps current may not be the correct one.
4.. Advance timing to 25*

I wont be able to road test today as its raining heavy but will post with some photos today of the set up. I feel like I am close on this as it runs great with no bogging when I do WOT. Just issues of engine stall when choke is wide open at idle.

That duration cam of a will need a ton of initial advance. I would block the power valve if you suspest it, JUST TO GET THE IDLE RIGHT, DO NOT DRIVE!! It sounds like your outboards are a little rich at idle by your description, and the center is not doing much. The idle fuel feeds in the center metering block could be plugged. I have fixed a similar problem by finding a metering block that I can see the brass idle fuel bleeds in, so I can add more fuel, .001 at a time. Most stock 6bbl blocks have hidden feeds, so no dice there. 8 psi could overpower the floats, pull the sight plugs and see. The fact it will not idle without the choke tells me it is lean, meaning power valve ok, could be pcv valve, likely a mixture problem. Sometimes lean smells rich to most people. A few things to check
Front carb
.078 throttle blade holes
.055 idle air bleeds
#34 metering plate with .036 idle fuel bleeds .089-.089 jets
Rear is same with#35 plate .036 idle bleeds .086-.093 jets
Center .078 throttle plate holes
.068 idle air bleed
Make sure someone has not drilled any of those, and the metering plates are 6bbl #34-35, the new replacments are not the same.
Mine idles clean with an old .509 mopar cam, I know outdated junk, stock plates, 3/8 turn on the
outboards, 1-1/4 on the center, and those stock drill sizes I listed. 3.5 power valve, 64 jet and a 4-speed. If I go 1/2 turn on the ends it gets stinky. I need a choke to start it, none once it is warmed up. It will die if you turn 1 center mixture screw in, so it is close.

Do not set the outboards to 1.5 out!!!! The way to do it is set the center to 1 turn, ends to 1/4-1/2, and adjust your idle fuel bleeds until it idles. My carbs sat on a 312/590 cam and did not need no 1.5 turns. The center should be 1-2 turns out, and 1 screw bottomed should kill the engine, with ANY holley, if the bleeds are right.

I would install the idle solenoid, as in original six pack cars.

What list # are your carbs? I'll look them up in my Holley master parts catalog and give you he stock jetting for the center carb and the part number for the outboard mixture plates and hole stock hole sizes, hopefully.
Me thinks someone may have mess with them before you got them
On the power valve the vacuum rating shouldn't have any affect on the idle unless you have the idle speed screw adjusted up far enough to make the center carb idle on the transition circuit, you can check that by removing the center carb and flip it over after draining the gas out of it and see how far the throttle blades are opened in relation to the rectangular slot in the front center of the carb throttle plate if you can see any of the slot below the throttle plates it is to far open and idling on the transition circuit
I check the power valves by removing them and then use my mouth and tongue to suck on them and make my tongue seal against the center hole, if the valve stays closed with my tongue on it is good, if it doesn't stay closed it is bad A ruptured power valve will make it idle rich all the time due to leaking fuel into the carb.
I use a vacuum gauge to check the idle vacuum and install a power valve that is one to two inches lower in vacuum, if it idles above 8.0 inches I use the 6.5 rated valves If it idles at 5.0 inches in gear like my old pump gas stroker motor did I would use either a 3.5 or 2.5
I used both in it and it work the same, not so on the 4.5
Do you have a pin vise and a good small (.011 to .060) set of drill bits? If so use the drill bits to see what size the bleed holes are on your carbs, the center ones are the idle bleeds and outboard ones are the high speed bleeds Post them on here and I'll look up which size they where stock , if I can find them in my catalog
I've owned, tuned and driven a bunch of stock 340 and 440 six pack cars with the stock carbs, they would idle great and drive okay with the stock jetting and so on. You can make those motors run a lot better by proper jetting and tuning
Open the outboards idle mixture screws to 1/2 turn and the center to 2 full turns out from bottom and then use the center carb mixture screws to get it to run as lean as you can when warmed up and set the speed idle at or below 1000 RPM so the center throttle plates are not opening up to the transition circuits
It is snowing here, hopefully it will not snow after tomorrow, we need the water but it is mid March
Good luck on this, you can fix it

I wonder if you have correct base gaskets under the carbs? especially the center carb.

That tells me you are very lean and most likely a bad vacuum leak or an internal carb problem.

center carb is 4375 outer carbs, front 4382 and rear 4383. I dont have the listing numbers as hard to read. Far as the base plate is concerned front base plate has been messed with as it was redrilled with new inserts to fit the screws. It was stripped and had to be drilled out. The hole is bigger than rear carbs and needle sticks out much further. I figure this one is easier to adjust since it's in the front. New base plate have been tough to find.

Your picture of the right side show the vacuum port for the rear carb booster is open. All three carbs need to have the vacuum ports connected through a T fitting. It looks like you have the center and front carb connected with a hose and nothing to the rear carb. They all three need to be connected together.

Hi center carb diameter is 1/16 air bleed hole, outer 3/64

they are all connected correctly. What you see is a vacuum hose that goes into the choke pull off disengaged so the flap stays closed.. I put a screw in it to stop it from air leak.

my bad.. I see what you mean but still no difference.

Here is what happened to me this past summer coming home from Carlisle. My six pack worked great on the highway but when i was almost home and had to stop the car didn,t want to stay running. After taking the center carb apart I found that there is a little ball that is held in place with a little brass strip in the accelerator pump housing which fell out. Put the little ball back in and laid the little strip in place and repined the little ears that hold it in and now run's like a champ. Like someone said it might be something little!!!!

If you mean the idle screws were drilled out it may be a problem, but as long as the engine dies when you turn the screw in all the way you should be able to get it to run. The idle screws in 6bbl baseplates are not the same as the regular metering block idle screws. Baseplate screws have longer thinner needles.

The center carb. came with Holley #63 jets in it, the 4382 outboard carb should have a Holley part # 34r-6153-34 metering plate in it and it should have had a .052 fuel inlet size in the bottom of that metering plate, the other carb # 4383 should have had a r34-8153-35 plate number in it with a .071 fuel inlet size hole on the bottom of it.
I have heard a lot of people on here say that drilling those holes out to.086 works good
My set of original six pack 1970 carbs like #63 jets in the center carb and .096 air bleed jets in the one side and .092 size air bleeds in the other. Those plates had the original holes plug off and where drilled out and tap to use Holley screw in air bleeds. that set up worked real well Once I got the fuel system straighten out with the proper size pre fuel pump fuel filter size it didn't want any richer jetting than it had
I did try richening up the out board carbs jet sizes by .004 and it slowed down, I didn't try leaning it down though
All the stock six pack center carbs I worked on didn't like a lot more jet size in them, maybe one or two sizes up or down, no more than that though
Take a look at your outboard carbs. metering plate numbers, both of them and post it on here to see if they are stock or been change like the center carb jets have been
Make sure that the fuel feed holes(channels) for the power valve haven't been plug off also
Let us know what you find

Ummm, I suggest before taking this advice you mesure your metering plate fuel restrictions, specs given here are wrong and are out of a holley book. Wrong for a 6bbl, correct for a 4bbl. I do not know why there is this discrepancy,
but there are 2 types of 34-35 plates, you must measure. #63 jets are fine. Cab are you saying .092-.096 idle air bleeds on the center carb, sounds more like super stock end carb main jetting, my 3 sets are all .068 idle air, center carb, .055 on the ends.

To all, I just posted on you tube on this issue. One thing I did discover is that plugging the air bleed holes on the outer carb with wire actually evened out the idle. I took it for a quick drive though it does not stall, its definatley running rich and some loss of power.
Far as the jet size, it's a 65 due to the size of the cam and is stroked out to 512. More and more I think it has to do with center carb not working properly. I should not have plug the outer bleed holes.
I am trying to keep the original metering block but I might just change it to 134-203 replacement and see what it does. I am pretty sure the outboard carb metering plates are both 34.

https://youtu.be/8X2MP8jzD3A

So you simply proved it is lean and needs more gas at idle. Now you say it is rich... well I hope so as you took half the air away from the emulsion tubes, and are drawing harder on the idle fuel feed restrictions in the end carbs, with the end carb idle screws at 1 full turn. It will be rich at 1 full turn. Until you measure the metering plate restrictions who knows what is in there. I suggest a holley carb manual by alex walordy so you understand how the idle works. I would say you need bigger idle fuel feed restrictions, made bigger .001 at a time. I am assuming the idle air restrictions are stock size. A metering block for the center carb that you can adjust would be good. I used a 600 or 650 double pumper plate on mine to get the drillable idle feeds. You adjust the fuel feeds .001 at a time until it idles with the center carb at 1 to 1-1/2 turns, ends at 1/2 max. Timing needs to be at least 25 on the crank and stable, not bouncing around. No magic here, the idle will take work, I am betting the center carb is open on the transition slots at idle, as a 512 needs more air than a 440, and I don't even want to get into fixing that.... but here goes. It would involve drilling throttle plates, not allowed on this board, most on here think any 6bbl with drilled plates has been modified, no it is factory. Bigger motor, bigger holes, .002-.005 at a time until it idles with the plates closed. Oh one more thing, that big hydraulic cam will not idle clean at 800 rpm like the big roller cams most guys use, so you guessed it, you need more air for that too, bigger holes. Now you know if you really want to fix it.

Not idle air bleeds, my carbs had .092 and .096 fuel restrictor, IE Holley screw in air bleeds acting as the jets on the bottom of the stock metering plates with the original metering holes plug off

Ok, you are right they do not like much more jet. I need to clean up my last post, no emulsion tubes in the outboard
carbs, might call them emulsion wells. Its where the fuel and air become an emulsion in the metering plate to start to become a burnable mix at idle.

I thought of something else you can check and reset if needed is the fuel, float level. Most Holley like and need the fuel to barely dribble out of the side hole when running at idle speed, if you look closely at your carbs you will notice that the outboard screws for checking the float level are higher than the center bowl is Don
t set them in the middle of that hole, that is to high
Let us know how your doing on fixing this issue, six packs rock when you get them right Which is not always easy

Cab,you got it backwards,the center is higher than the ends,better check your !

I think I will try changing out the center metering block, new air/fuel mixture screws and gaskets. I still think it needs more fuel from center carb. I will post soon as the new metering block arrives. I appreciate all the advise as it seems alot of interest on the topic and outcome. I sure hope I find whats wrong and dont let anyone down. It would be great reference for someone else down the road.

Me thinks it depends on what part number carbs and year your working on

Cab,I've been restoring sixpack carbs since the early 90's,"never" had/seen any that the end sight plugs were higher than the center,all of these are as I said.

Bill after looking at all the carbs
How do you remember whose are whose . LOL ..

to the OP .. get rid of that teflon tape on the connections its gonna end up on your needle seat . , it doesnt do anything to help for leaks ..

I agree...with the duration of that cam, the distributor needs to be reworked for about 16-18* initial and all timing in by 2200 RPM...makes a HUGE difference. Mine is a 496 with 6 pak and a Comp XTQ294 solid 264-270* duration. Idles fine in gear at 1000 rpm.

I am still waiting for the replacement metering block to arrive. I guess with this coronavirus thing going on its causing havoc with shipping . It says 27th, I should receive.

Couple things i did try while waiting,
I put in a new set of jets on the center metering block. I had a spare 65 jets and drilled out to .075. I did not make much of dofference. I did notice and can here fuel leaking into the manifold when i turn off the engine which told me fuel float level was too high. Adjusted that and it seems to run bit better and didnt rabbit.

I also did advance timing 20°helped a little. it holds steady rpm while no load, however on a road test it cuts out when coming to a stop again.

Running out of options.

The OEM six pack center carbs that I have worked on seem to be real sensitive to the jets in them, try a set of stock Holley # 63 in yours like they came with

I just dissembled a set of carbs today that had the gasket on the left as the center metering block gasket,owner told me it always was rich,leaking fuel and couldn't get idle below 1200 rpm. I've had more than one over the years that someone changed gaskets/rebuilt that had the 4160 4 bbl gasket instead of the correct 2300 gasket,easy mistake.

On another note,I finished my 4 spd bird in 1992,cam is old Direct Connection Street Hemi grind,280/474,end carbs have unmodified correct 34 and 35 metering plates and #.065 main jets,doesn't run rich,no black exhaust tips,about 17 mpg if you drive sensibly, runs like a clock, and hasn't been touched in 20 yrs.

I wish that was the case but I have the correct blue gasket.

You ain't even close to being out of options, you have barely started. You will never need more than .065 main jet on a center carb, a bigger main jet has almost zero effect on the idle. Until you get it to idle with the center throttle blades closed, you will have problems. I hope the new metering plate has bigger idle restrictions, or it will make no difference. I explained earlier how to do this.

From your description, sounds like a vacuum leak. Jets, metering blocks, power valves, mixture screws, etc etc, are all important, but none of those items will be "tuneable" if there is a vacuum leak. Easiest way to check is to put some water in a squirt bottle, and with the nozzle set to "stream", apply light amounts of water to the carb bases and intake gasket areas while engine is running. Any breach will result in sputtering showing you quickly and safely where the leak is. Avoid using carb cleaner, brake cleaner, or propane to avoid a fire hazard. Keep in mind that even if you rule out an external vacuum leak, it's still possible that there could be and internal leak in the carb(s). Don't worry a little water in the cylinder wont hurt anything...Good luck.

And one little note for reference,the only center car throttle blade with hole is the 225,used in the 69 1/2 carbs only,all others used the 222 blade,no hole..

Looked thru all my extra junk, you got me on the center throttle plates....almost ....2 of my 1970 sets have 225, 2 have 222s. All are 4375 list, It appears that if it had holes 225s it got a 6170 metering block, 222s 6020 metering block. All 4 sets have the same idle air bleed.068 same high speed bleeds.028, same pvcr .046. The only thing I see is that the no hole carbs have the curb idle screw turned in 2-3 turns more, blades are open more. Anyway, never looked at them all side by side, learn something new. I have no 69-1/2 carbs, what # rear throttle plate do they use, and what size hole is in them?

,All front and rear plates are either # 199 or # 226,big block,the # 199 is big block only and has a smaller hole than the # 226,small block is # 226. The # 199 plate was used as replacement due to supposedly sticking # 226 in early production but not sure of when the change was made,most all I get in have the #226 plate.I have all the original Chrysler engineering,installation,specifications and adjustment procedures from 1970,I'll go through it when I get a chance and possibly clear things up a bit. If you don't have and can find one of these Holey manuals buy it,you'll never need to second guess anything,it's all in there.

.Below is metering block application and blades,no exceptions .


# 6170 69 1/2 A12 225 throttle blade
# 6020 70/71 440-6 222 throttle blade
# 6610 70 AAR/TA 222 throttle blade

I'll assume it's a somewhat hard stop?, if so, my experience is this is usually high fuel level(s) as the fuel can run up/slosh up the vent tube and spill down the throat(s) either ragging out the idle and or stalling the motor, might try lowering the float levels just below the sight hole, try and see what happens, easy and no costs... if your running a stock 6 pack air cleaner, check the underside of the lid, clean it, take the car out, run it as you do causing it to stall, immediately check the underside of the lid for wet gas to possibly ID the carb(s) causing this

If that's the case? perhaps the vent baffle is missing inside the carb?

You might find you need vent tubes to prevent this condition? Holley has various lengths, or make your own out of tubing, or a larger Holley aftermarket vent tube baffle inside the bowl?

Just throwing it out there...

That why it is good to use clear sight plugs in the outboards to set the float level when tuning. Take them out after tuning because they will turn to crap after being exposed to gas.

It looks like holley still sells the book. Are you telling me that it includes part numbers, or does it have the actual measured sizes for the restrictions like high speed bleeds, idle air bleeds, throttle plate holes, metering plate holes. I will buy it if all restrictions are listed. I can tell you for sure the 4375 I bought from direct connection in the 80s had 225 blades, and a 6020 metering block. We know as fact the current over the counter #34-35 metering plates have the wrong size restrictions. Holley did not always get everything right. As for the OP... we know he needs more gas at idle, as plugging the idle bleeds makes it quit dieing, I think he needs more idle air also to get the center blades closed, but I ain't standing there to see how far they are open, with that cam quite a bit I would bet.

The book contains illustration of carb,all related parts pictured and reference and part number for every piece.It does not contain the various air bleed and restriction measurement. The Chrysler engineering information that I mentioned above has that,when I get some free time in the next few days I'll see that you get it.

I think this is something I need to look further. I will pull it apart perhaps later this evening and post some pictures. If I can recall the outer carb throttle plates were 220 and did have holes. Cannot remember the center though.. I am wondering if this is the reason why I cannot tell if there is a vacuum leak. I did everything everyone suggested on how to test for a leak. Nothing worked and wondering if that is the reason. It is constantly drawing air through outer carbs or more air then it should.
I have ordered new sets throttle plates from Holley 1 3/4 size. They do not manufacture the originals anymore.
I should be receiving metering block today. Lastly, I ordered a new base plate from promax with idle screw positioned off to the side. Cost of parts keep adding up..

That would be great, thank you. Kind of wonder if that is why some setups run perfect, others not so much, wrong pieces to start with.

Like I mentioned above,finished this in 92,took them off and had them refinished 2003,put them back on with same adjustments when the came off,never had to do anything,still runs same as it did in 92.

Ta all..
Thanks for all your help. I finally fixed the biggest issue with idling and cutting out when choke is wide open. i Changed out the metering bock it did the trick. Replacement part from Holley was134-203 if anyone is having similar issues. Its completely different with imultion holes in different locations but working good now. Not sure what's wrong with my 6020 original metering block. Now I just need to tune it which am sure I can figure out. It's running bit rich but i think i know the reason why as have the outer carb mix screw at about 5/8 to 3/4 turn. I will wait till I receive the promax base plate before I take it apart again.
I put the 6.5 power valve back on and #65 jets. Also I was wrong on the throttle plates. They were 222 on the center and 226 for outer carbs.
Here are picture of two metering block and see the difference.

Good to hear.👍