#81  
Old 12-12-2017, 03:02 PM
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Typical carbs today, which you are talking about, I believe), are in a Advertising "Dream World".
For over 50 Years 20.4" of water - 1.5" of Mercury (Hg) was the Carburetor Test Standard.
Then Carb Modifiers read that Smokey used 28" of water test pressure for flow testing because it matched numbers on HIS DYNO. Just because the numbers matched on one guy's dyno do not mean that all dyno testing and Flow bench testing has to be done at 28" of water.
Bob Mullins had World Championship Hemi engines where he flow tested the heads at 3" of water. A BUNCH OF THEM. So which is closer to reality for a large port Head, use a small block port Test Pressure number or use a 500 cid HEMI flow test number. Never could understand why people could not see that 28" is not a Magic Flow Number for the test pressure. But Smokey wrote it in HIS book so it must be Gospel. I knew Smokey personally, RIP, and he was not a Rocket Scientist, just a really hard working guy.

But back on the question. Ok your actual 750 cfm carb flows 950 cfm at 28" of water. REAL 750 cfm carbs work well when the engine wants 700 cfm worth of flow. DOH!

So the 950 CFM number you ask about is a number used for advertising games.

Holley had to play that game because Barry Grant and other Modifiers were playing that game. People would see a 750 CFM carb vs a 950 CFM carb and say GOT TO HAVE that 950 CFM carb for bragging rights. The only true 950 cfm rated Holley was the 3-Barrel unit flowed at 20.4" inches of water. But it also was a Vacuum Secondary carb so the engine and Primary Vacuum Signal actually told it how much air to let into the engine.

One final Comment, on the airflow deal.
When we ran the Booth and Aarons Pro Stock 350 cid engine on Holleys 10,000 rpm Water Brake Dyno at 3500 rpm the engine would barely idle. There was a Fuel Reversion Cloud 3 feet over the carb inlets at that rpm. At 5000 rpm the "cloud" disappeared and the Engine finally was not pumping fuel back out of the carbs/engine. At 10,000 rpm the engine was making sweet music. Carbs Individual Runner Intake and single Carb Bore were right where they wanted to be.

So why did Holley not go into production with that system? Well you blow a couple of Glass Front Ends off of Chebby Vegas going down the track and
the owners are not happy, no matter how big the carb cfm is.

So then we did the Pro Dominator Intake.
Much more like Tunnel Rams you have seen for many years now. Not like the Pontiac NASH TR intake. Nice large Plenum.

It all has to do with PHYSICS and where the carb matches what the engine wants, guys.

Tom V.

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Last edited by Tom Vaught; 12-12-2017 at 03:08 PM.
  #82  
Old 12-12-2017, 03:44 PM
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Quote:
Originally Posted by Tom Vaught View Post
Anyone recognize this Holley carb?
It has an interesting feature.
It was designed in the early 60s.

More on it and Booster Tech tomorrow.

Tom V.
They made their rounds in restricted circle track classes....to be banned later as many innovations are.

  #83  
Old 12-12-2017, 04:53 PM
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Ok, STEELCITYFIREBIRD, YOU REMEMBER THE CARBS. 650 CFM 2-BBL ANNULAR DISCHARGE VENTURI.

Some years later, 2010, I was asked to come up with a very efficient EGR Gas Mixer that could be installed after the Turbo Compressor and before the Throttle Body. So this is what I came up with: https://www.google.com/patents/US20110162360

You will have to look at Image #4 of the Patent.

The EGR Mixer has a lot of features of that 6425 2-BBL carb, LOL! You will also notice the Patent says for HIGH BOOST applications.

Tom V.

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  #84  
Old 12-13-2017, 08:18 AM
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Today going to talk about Holley Carb Bases.
Why they are machined the way that they are and ways to identify different bases and their circuits.

Holley Carb Baseplates and the difference between "Old School" Vacuum 3310-2 type Idle Circuitry and Double Pumper 4779-6 Idle Circuitry.

Also going to show how we used to mod the Baseplate for 4 Corner Idle Circuits. There is a lot more to adding "4 Corner Idle" capability on a 3310-2 and many times it is not really needed for a "Warmed Over" 3310 type carb.

Picture #1 (left Pic) shows a aftermarket base for a Chevelle 3310 (780 cfm) vacuum carb style idle circuit and a Corvette 850 CFM vacuum carb. Several things to notice:

1) The Aftermarket Base has the idle feel holes in the Base set up for both carbs. The Idle Feed Holes on a 850 CFM Carb are straight across from each other. The 600 to 800 cfm carbs have staggered Idle Feed Holes in the base. If you look at the Base you will see that the base has the 8 Mounting screw holes, it has the machined grooves in the base that go (Look at the upper part of the picture) Idle feed holes down toward the lower idle feed holes but the slot does not actually connect the Idle feed Holes together. Picture number #2 will show that detail in a bit.

The "staggered" Idle Feed Holes were used on the 780 CFM carb base 3310-0 and used a 1-11/16" diameter Throttle Blade marked with a 172 number on the PRIMARY Blades. The Secondary Blades were marked with a 173 number on the Throttle Blades. That same Throttle Base Blade could be used on a 650 CFM Double Pumper Carb, 3310 Vacuum Carbs, and all the way up to the 800 CFM Double Pumper Carbs.

The 850 CFM Vacuum Carb and 850 CFM Double Pumper Carb got a unique #180 Throttle Blade in the old days. Along with that previously mentioned different Idle Circuit hole position.

So that is why the AFTERMARKET BASE in Picture #1 has both holes machined. So it will replace both series bases and it probably uses the very slightly larger 1/16" bigger 180 throttle blade.

Picture #2 (Middle Pic) shows a Holley Double Pumper Base designed for a 650 cfm #4777 to 800 cfm #4780 carb. This base is set up for 4 corner idle because you can see two solid blugs pressed into drilled holes in the base that separate the machines "slot" mentioned previously.

As you can see the idle holes vs the Transfer Slot holes are "Staggered" as mentioned earlier. You can also see the "PV "Blow-Out" Protection ball and retainer at the top of the picture close to the "A"). The Secondary side does not have that set of parts so that means the Metering Block on the secondary used a Blocked Power Valve Plug or was not drilled for that PV Install capability.

The base also has Throttle Blades with LARGE "Idle Air Bleed Holes" drilled, so this is a older base that was made before the recent Holley IDLE-EZE parts were available.

SPEAKING OF THE BASE MOUNTING SCREWS AND THE 8 MOUNTING HOLES DRILLED IN THE BASE. (YOU ONLY NEED 6 TO HOLES THE BASE ON PROPERLY.
NEVER INSTALL THE MIDDLE OF THE BASE TWO SCREWS THAT ARE CLOSE TO THE 4 CORNER IDLE CIRCUIT "PLUGS" ON AN OPEN PLENUM MANIFOLD. The screws could vibrate loose and drop into the engine combustion chamber/wedge the valve. I Never install them in any Holley Carb I touch.

So with the idle circuit slot plugged (on both slots), you can use the 4 Corner Idle Capability and turn your Mixture Screws out 3/4 of a turn on the screw vs 1-1/2 turns on the 2-corner idle carbs.

Picture #3 (Right Pic) shows the OEM Idle Feed SLOT in the base. It connects from the Primary Idle feed Drillng and you can see that it goes to left side of the picture but then stops.
You can also see the Transfer Slot machining in the holes above the idle circuit holes.
"Fuel Bowl Purge" on the rear bowl of the carb is handled by a very small drilled BELOW the Transfer Slot in the base. This allows the carb to remove stale gas if the Secondary barrels are not used for any period of time.

So that covers the basics on the different bases, why the fuel circuits in the base are different for a 2 corner idle carb vs a 4 corner idle carb, The Throttle Blade sizes for easy identification at a swap meet, and Fuel Bowl stale Gas purging.

Tom V.
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Last edited by Tom Vaught; 12-13-2017 at 08:23 AM.
  #85  
Old 12-13-2017, 07:23 PM
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Smile Tuning my 6910 Spreadbore Holley

Trying to be a good student here, Tom.

Carb is on a RAIV intake w/1-inch phenolic spacer, no heat riser in use, mild 462, 9:1 compression, HFT single pattern cam 228degrees 480 lift on 114 centers, Hooker comp headers. Floats are level, all settings are 'out of the box' correct except rear jets are #80 instead of 86. (Too scary to check WOT w/o a helper in car to watch gauges!)

In order to maintain a 'square' window @idle discharge, The throttle must be completely closed w/zero tension on the idle speed screw. I have opened the secondary throttle blades 15/16 of a turn from zero tension and that gives me a nice 750 RPM idle w/14.7 AFR. I have reduced the IFR's with a piece of .008" wire.

How am I doing ???

  #86  
Old 12-13-2017, 07:47 PM
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Doing Great. Sounds like you have the basic idle Fuel/ Air right where you want it. Is your meter a Lamda meter (fuel/air) or a Air/Fuel meter.?
You reported 14.7 to 1. Assume Air/fuel.

You could have slightly more height vs width on the Transfer Slot window and be able to back off the Secondary Screw to 5/8 or 3/4 turn from zero. Then you might have a SLIGHT tension on the Primary Screw (There should be some light tension on the Primary Screw spring to hold the Primary Screw in place (keep it from moving).

Sounds like you are real close on the idle mixture and ready for the Transfer Slot/ Transition portion of the off idle curve.

Tom V.

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  #87  
Old 12-14-2017, 01:04 AM
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Thumbs up tuning my 6910

My meter is an AEM Air/Fuel. Since I am not racing the car, I use this instead of track times/time slips for tuning.

As I pondered this stuff while waiting for the sandman to show up, I thought about the same thing: split the 15/16 between the idle speed and secondary throttle. I will start with your suggestion. Having the screw installed from the top sure makes it easy to do this!

Thanks for the response. Soon I will transfer the A/F meter to the old carbed Triumph motorcycle. This forum is truly a great place to hang out!

  #88  
Old 12-14-2017, 07:35 AM
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If you have a lean issue during off idle transitions then the A/F Meter should pick up the lean condition and you can work around that with a bit more tuning on the blade positions.

Tom V.

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  #89  
Old 12-14-2017, 08:30 AM
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Here is a thread from the Turbo Forums with a guy asking about how to convert from a 2-corner idle to a 4 corner idle configuration.
https://www.theturboforums.com/threa...r-idle.340643/

1) Mr Bowtie Guy broke the ear off on his 2-corner idle base plate. So he decided to bolt on a 4-corner idle baseplate. So now he has the mixture screws out 5 turns on the Primary Side
Metering Block to get the thing to barely run.

"Ok.... after 7 hrs of searching the web... I want to convert the carb to a 4 corner idle carb.... but I havent found ANYTHING yet on how to modify the carb body for it......"

"Ok.... I found a diagram showing me the holes I need to drill in the body, here it is:"

(Same picture I posted up in our thread on Carbs showing the different main body drillings.)

"Im a idiot....... For the people who search this thread..... On the secondary side of your carb main body, drill both number 3 holes (in the diagram posted above) to the same length as the primary side holes.... as long as u have a 4 corner idle baseplate, and a secondary metering block that has the idle adjustment screws... this will make it a 4 corner idle carb...
Bowtie Guy"

So in post #7 I replied I am Boost Engineer on the Turbo Forums.

"I was hoping you were going to post up in here Yeah you just described my setup lol. All idle air bleeds are the same size, and its the happiest with the idle screws around 3/4 of a turn out :2thumbs: From a stone cold engine, I can pump the gas twice, hit the key, and it'll run without having to run the throttle I could never get it setup like that with a 2 corner idle setup.... Been tuning it for like 4 months now and it runs just as good as a efi setup would I'm very pleased :cheers: Thanks to all the info on the turboforums of course :bow: Thanks guys :2thumbs:
Bowtie Guy"

So he was a happy guy after searching on the web for hours, and not getting any help otherwise.

So the post today is about part 2 of the 4 corner Idle Conversion Process.

1) He had a 4 Corner Idle Baseplate (like I showed in one of the previous posts so that saved him modifying a stock baseplate. 4-corner idle baseplates can be purchased from Carb Builders like Shaker455. He buys from the same source I do. Now you have a new part and you have not screwed up your stock 2 corner idle baseplate that you could sell to a guy like Bowtie Guy who broke the ear off his.

So now we have a 4 corner Idle base plate and you know the drillings and what they do.

So then we go to this quote:
"Im a idiot....... For the people who search this thread..... On the secondary side of your carb main body, drill both number 3 holes (in the diagram posted above) to the same length as the primary side holes.... as long as u have a 4 corner idle baseplate, and a secondary metering block that has the idle adjustment screws... this will make it a 4 corner idle carb..."

A bit more info here.
There are two drilling in the main body for each idle circuit. One the primary side the two drillings meet each other. A drilling from the Throttle Plate side of the mainbody and a drilling from the Metering Block side.

On the Secondary side of the main body the vertical drilling (from the base plate side upward into the mainbody is ALREADY the correct length. The drilling for the Horizontal drilling on the metering block side is slightly short and does not intersect the vertical drilling.
So Mr Bowtie Guy figured it out that if he measured the horizontal drilling length on the #3 holes on the Primary side and drilled to the same length on the secondary side he would JUST BREAK THRU into the vertical drilling.

If he had tried to guess where the two met he might have drilled right into the booster/throttle
air flow passage and then would have had to somehow plug that screw-up. (Saw a young Holley Engineer do that one time but I helped him fix the deal later.)

So Bowtie Guy already had another 3310 style Primary Metering Block for the secondary side so no mods there.

So now he just needed to make the secondary
Idle Air Bleeds in the Mainbody the same size as the Primary Idle Air Bleeds. And set his Mixture screws to 3/4th turn out.

So he did that and I repost his final statement:

Mr Bowtie Quote: "I was hoping YOU were going to post up in here Yeah YOU just described my setup lol." All idle air bleeds are the same size, and its the happiest with the idle screws around 3/4 of a turn out :2thumbs: From a stone cold engine, I can pump the gas twice, hit the key, and it'll run without having to run the throttle I could never get it setup like that with a 2 corner idle setup.... Been tuning it for like 4 months now and it runs just as good as a efi setup would I'm very pleased :cheers: Thanks to all the info on the turboforums of course :bow: Thanks guys :2thumbs:
Bowtie Guy"

So here you have a real live thread on how to mod a 2 Corner Idle carb for 4 Corner Idle and how happy the guy was later.

Tom V.

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  #90  
Old 12-15-2017, 09:00 AM
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Circuits of a Holley Carb
Holley Carbs (as well as other brands of carbs) have had over 100 years of development time to figure out what is the proper air and fuel mixture during any vehicle/engine load event and what the Air/Fuel Mixture needs to be for most applications

Some writers say there are 5 major circuits in a Holley carburetor, but I would disagree on that simple statement. There are more.
These 'BIG 5 Circuits' are reported as:
The Idle Circuit
The Transition (also called Transfer) Circuit
The Main Circuit
The Power Enrichment (also called Power Valve) Circuit
The Accelerator Pump Circuit
(Everyone seems to forget about the Fuel Bowl(s) and the proper fuel height necessary in the bowl in relation to the different circuits.)
(There are other circuits like the Choke Circuit, the Ported Vacuum Circuit, the Manifold Vacuum circuit, and the Secondary Vacuum Control Diaphragm Circuit that come into play at different times too.)

I have seen Carb articles where writers try to make things simplier for people and segment the different modes of the engine and Fuel System Demand to precise areas. Unfortunately it does not work that way.

You will have "cross-overs" where several circuits are working at or very close to the same time depending on the vehicle event.
But in simple terms this is how it goes:

At Idle, you have the on the Air and Fuel side of the equation you have the Air Passing by the Throttle Blades and the Idle Discharge Port and the lower edge of the Transition Slot Port.

Just Above Idle you have the Idle Circuit functioning and the Transition Circuit functioning, as well as a momentary function of the Primary Accelerator Pump Circuit.

During the Cruise portion of the Drive Cycle you have the Idle Circuit, the Transition Circuit, and the Main Circuit all working together.

During the Power portion of the Drive Cycle you have the Idle Circuit, the Transition Circuit, the Main Circuit, and the Power Valve Circuit involved.

And finally (using the simple discription of how a carb works), during Severe Acceleration Events, you have Idle Circuit, the Transition Circuit, the Main Circuit, and the Power Valve Circuit involved. The circuits act in a "Step Function" as the engine/vehicle transitions thru the acceleration curve to top speed.

How you control (adjust) these circuits is based on where the parts are in relation to each other.

The Basic Air/Fuel Mixture is controlled by the Idle Mixture screws, the Throttle Position Screw, and the Engine Event Profile of the Camshaft. (Radical camshaft events can cause severe Exhaust Gas Dilution of the incoming intake charge at idle).
Mild camshaft profiles will have a much smaller effect on the engine behavior at idle.

The Transfer Slot vs Throttle Blade Position on the Primary side of the carburetor, as mentioned in other posts, needs to be at a precise location for best 'Transition" thru the circuits. You can typically adjust this to a "Rule of Thumb" position and get acceptable performance out of that circuit.

At the same time the engine needs a given amount of air flow thru the engine, typically 15 to 19 cfm, to keep the engine at a acceptable idle rpm. Large engines will get the higher cfm idle flow.

When the engine/vehicle finally get to the Main Circuit and the vehicle is motoring down the road, as you can see a lot of other things happened between the vehicle at rest (engine off) and the engine at Cruise RPM.

You calibrate the Main System based on the Main Air Bleeds and the Main Jets. You can actually dial the circuit in to where you CAN get very acceptable Fuel Mileage from a Holley carburetor contrary to popular believe that the Holley Carb is a "Gas Hog".
Ideally this is by using a smaller Main Jet and dialing in the Power Valve Circuit for the addition fuel required. More on this tomorrow.

So here is where I stop today.

Tom V.

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  #91  
Old 12-15-2017, 06:50 PM
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Thumbs up POST #88

Don't laugh too much, but this is quite nearly a 'goes to church on Sunday' only car. So I tune/adjust during the week and evaluate on weekends. Keeping a log of all this is very helpful. I will certainly keep your comments close by.

Don't know if I will ever be able to get a good fill-up at the station after reading everyone else's experience trying to pump gas into these 'behind the license plate' fill tubes. So there goes my keeping track of fuel economy. But most certainly that is a much lower priority than enjoying the ride !! Living waaaay out here in rural America means I have a 'flammables' shed and most often add fuel 5 gallons at a time.

  #92  
Old 12-15-2017, 09:30 PM
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Northwest at minimum puts you in the Las Vegas area and maybe if you are really far northwest up in Beaver Dam country.

Nothing wrong with taking a Pontiac on a Sunday "Go to Church" trip.
Especially out where you can "See the Sky".
I really miss that part of the country at times.
Get a proper tune on that Holley and it will knock down some mileage on that 5 gallons of gas.
Tom V.

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  #93  
Old 12-16-2017, 09:25 AM
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Wink NW AZ

Last week I actually went past the Yucca proving ground on a trip to The London Bridge.

  #94  
Old 12-16-2017, 12:19 PM
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I decided to talk a bit about Carburetor Testing based on your post #93 today, unclescratch.

I originally worked on carbs (Tri-Power Carbs) and AFB carbs for myself. I would fix (rebuild) a Tractor carb, Combine Carb, or Irrigation Pump Carb as needed to keep the system running.

The I went to the First College and they had an Automotive program for the "Farmer" Kids as well as Engineering programs for the Aviation, Electronics, and Mechanical Engineering Guys.

So I could slip in and see what the Auto Guys were doing with their stuff. The First School had a Rear Wheel Chassis Dyno. Amazing that a 325 HP Chevelle 396 engine would only make 275 HP on the Chassis Rolls. No matter how well you tuned that "Rotten Chester" Carburetor.

I stuck with the Physics, Statics/Dynamics and Math side of the deal for the most part because you could use those to explain carburetor Function and Engine Function. This was before Neal Chance decided to create the simple Superflow 110 Flow Bench. His first bench was good for about 10-12 inches of water and 110 cfm max flow.

Course the OEMs (like Ford) had Flow Benches that could go up to 5 inches of Mercury test pressure at WOT on the Carb (68" of water).

Holley carbs (WW-II) Flow Bench could do 3500 cfm at 20.4 inches of water.

But the Flow Numbers and the Physics apply. So the test data is not as important as how you run the test. Is the test VALID?
That being said, My Old Boss, Jim Clarke used to say, "One piece of good data is worth 10,000 OPINIONS".

So I went to a bunch of Colleges/Universities as I traveled around the country and the world and
basically every Professor had an agenda (along with teaching) "I want to sell the Book(s) I wrote"
So Smith would sell his book, Heywood (MIT) would sell his books, Ellenger would sell his books,
and of course even some of our members have sold books in the past.

So I had an Opportunity to work on Draw-thru Boosted Carbs as well as Naturally Aspirated Carbs (tested on Rear Wheel Dynos and "Air Box" Flow Benches, and Engine Dynos. Lots of Tests.

Then I went to Work for Ford on a Turbocharged 1979 Mustang Engine Program. The Lab I worked in was actually more like a massive Testing Building.
Many Chassis Dynos (all certified by the Government (EPA) for accuracy).

A Garage where 40 vehicles could be "pre-conditioned" prior to testing. A garage with 20+ vehicle lifts. Lots of Mechanics, Technicians, and Instrumentation people all there to support the testing and a shift of Engineers who controlled the testing and how it was done. Try to CHEAT on the Emissions/F.E. Testing and you spend 15 years in prison. There are a few Chrysler Guys who will get a chance to visit the "Grey Bar Hotel" for years based on their cheating.

But we (as Engineers) managed the Testing and signed off on the accuracy of the data and how the test was run.

Then I swapped jobs and went to work for Ford Truck Operations. Lots of Fun Projects there.
I did the first Lightning Truck prototype. I did the first Supercharged SVT Lightning Trucks.
But where I really was happy was when they asked me to fix a Emission System on a small
Ranger truck that was failing emissions in production. By then they were well into the basic
EFI calibrations and no one knew how to do carburetors (that worked with emissions systems).
The Japanese had originally calibrated the trucks for Ford and ASSUMED A LOT OF THINGS) on
how Carburetors worked with Emissions components. They made 3 critical mistakes:
The WAY THAT CARBS ACTUALLY WORKED, THE WAY THAT A CARB WITH THE WRONG CALIBRATION
CAN KILL CATALYSTS AND OTHER PARTS, AND THE WAY THAT COMPONENTS THAT INTERFACE WITH
THE CARB CAN FAIL DUE TO POOR SELECTION OF PARTS. Kind of like a Racer killing a lot of parts making mistakes.

So I worked on the problem with a "Honors Graduate" out of the University of Michigan and we came up with a "FIX"
before the EPA slapped us with a $10,000 fine for each vehicle that was not complying with the standards.

People used to say, "they would not really do that Tom." Well Chrysler/Fiat has paid BILLIONS in FINES for their deal.

So to cut to the chase, the issue was fixed and we moved on. They gave me a "FREE Vehicle" for that deal. What does a vehicle cost a company?
$10,000 fine times 18,369 vehicles. A lot more money.

But my best Carburetor Job at Ford was certifying some Econoline Vans with Holley carburetors (351W engines) at High Altitude.
Denver High Altitude Emissions Lab. Flew out there (after doing the initial Emission testing at Dearborn Mi), Tested the engines/vehicles on the "Emissions Rolls" (Dynos) and then did drive evaluations up in 'God's Country' in the Rocky Mountain National Park (Estes Park, Co.).

So yes, unclescratch, I have spent time at Yucca Proving Ground and stayed at The London Bridge Hotel in Lake Havasu City Arizona, like you.
Did you take the "boat up the canyon" trip while you were there?

So One Piece of Data IS worth 10,000 Opinions.
Some have lots of Opinions on how carburetors and Superchargers work.

Tom V.

Two comments about Writing Books for people. We are fortunate that we have people like Jim Hand, Cliff Ruggles, Rocky, Jim Wangers, Pete McCarthy, and others who were able to pass on very good info in their books. My boss at Holley (Mike Urich) wrote several Holley Books, A couple of Friends: Hugh Macinnis and Don Hubbard have written Turbo Books. Craig Hendrickson and Kern O wrote ("Mini" Books) each month with the HO Racing info.
They did it because they wanted to Share Information (as Craig H) has mentioned to me several times in our phone calls to each other.

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Last edited by Tom Vaught; 12-16-2017 at 12:47 PM.
  #95  
Old 12-16-2017, 11:30 PM
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I was looking over some Internet info from HOLLEY and I can across this PDF File.

The old Holley Catalogs had basically the same info so I did not pay too much attention to it at the time.

I see tonight that it has some good info that might help PY members:

1) Renew an Trick Kit numbers for specific Carb List Numbers

2) Needle and Seat Part Numbers

3) Pump Shooter Sizes and Vacuum Diaphragm Spring (Color of spring used)

4) Base Plate Part Numbers (if you want to order a 4 corner idle piece , for example

And then it has the info that I have seen for years in the catalog:
Bowl Numbers, Metering Block Numbers, etc.

Here is the link to the PDF File

http://documents.holley.com/techlibr...al_listing.pdf

Lot easier to read if you expand it to about 300%

Tom V.

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  #96  
Old 12-17-2017, 12:06 AM
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Tom,any idea where you can get info for carbs not on the list?Would like metering block numbers.Tom

  #97  
Old 12-17-2017, 10:17 AM
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Tom S, Another reason why I did not post that PDF info earlier is because some would assume that that is ALL of the info on Holley carbs.

In an earlier post, I mentioned the actual Holley "RED" and "BLACK" Carb Reference Manuals (only went to Holley Employees or Holley WDs typically).

So You PM me the Numbers for the Carbs you have questions about and I will try to send you the info on the Metering Blocks that came on those carbs.

Tom V.

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Old 12-17-2017, 04:28 PM
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Holley Carb Info back to you Tom S.

Tom V.

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  #99  
Old 12-18-2017, 09:02 AM
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Here is a nice little short article on the Holley 6-Pack 2 BBL carbs. just enough info to wet your taste buds a bit. I just picked the article out of the air.

http://www.rodauthority.com/news/his...reproductions/

The 6-Pack System can in two versions:
A production Vacuum Secondary version used on Mopar vehicles and Chevrolet vehicles, and also different versions (Mechanical and Vacuum) used on a number of Ford Engines over the years).

Ford had the 289 SB Ford set-ups, the 390 and 427 Ford set-ups with mechanical linkage, and a rare "production run" of NASCAR 366 cid Vacuum Secondary induction systems. 500 systems were made. Less than 20 systems out there today. Most were destroyed after NASCAR refused to allow the carbs to be used.

The Corvette got the 435 HP engine with 3 Holley 2-BBLs.
The Mopar Guys got the 6-Pack systems in a variety of vehicles.
The Ford guys got the "Tri-Power" set-ups in a lot of vehicles (early 60s days). (before they went to Dual Quad Holleys).

I am amazed at the prices that Holley wants for a repop set of the carbs today.
Almost $900 for the center carb alone.
$500+ for each end carb.
(I bought complete (new) Holley carbs in the boxes for 1/2 that price years ago and that was too much money vs slightly used.)

So I will post a Picture of a Holley Vacuum 6-Pack System for you to view.

I personally own the original Dyno Carbs used to generate the HP advertised rating for the MOPAR 375 HP 440 cid engines. They could be considered "Master Carbs" as everything on the carbs was verified on the dyno and air box. But a "Master Carb" is typically used to verify Production Carbs meet quality checks and match the Master Carbs calibration within specs.

More on Holley 6-Pack set-ups to follow.

This website has some good info on the rare Tri-Power systems (Ford mostly The web guy is a Ford Guy)
http://ford6v.com/ford-6v-tech

"351C 6VFORD 366 NASCAR ENGINE PROGRAM
Bob Champion’s 351C , The Cleveland 6V intake manifold. According to Tom Vaught, recently retired after 39 years as Ford Motor Company’s Boosted Engine Design Engineer and former Holley Engineer on the design team responsible for the development of the Holley Carburetion for the Cleveland 366 6V intake manifold, this 6V carburetion program came about through Ford’s 366 NASCAR Engine program where they built 500 366ci Cleveland motors with 6V intakes for NASCAR competition, only to have NASCAR disallow their use, causing Ford to physically destroy all the intakes. As apart of the Ford NASCAR 366 Engine program, Tom Vaught of Ford Motor Company (Holley Carburetors then) was a member of the design team that built the Holley 2300 6V carburetors for this special Ford project, using Holley 2300 vacuum secondary 6V carburetors.
During the testing, it was determined that the 1350cfm flow of all three carburetors was too much air and fuel for the Ford 366 program so these carburetors were sleeved for the Ford NASCAR 366 Program. After the comprehensive destruction of the 500 original motors, intakes and 1500 Holley carburetors, very few survived. The few in existence today were hiding on shelves and missed the actual Ford directed physical destruction.
Recently, a single Holley Sleeved 6V carburetor was sold with one of the very few 4296V intake manifolds still hanging around. This intake manifold was an original which had remained in the care of Buddy Barr Castings in Los Angeles , being sold in late 2004 to a Ford collector in New Mexico. Below are several pictures of the original Holley Sleeved 6V carb which belongs to Eric Hirengen of Farmington, New Mexico. This carburetor is an ultra rare piece. When Ford cancelled the Ford 366 NASCAR program, they decided to abandon the Holley 6V carburetors which they had Holley develop for them. Holley then offered them to GM and MOPAR. GM was not interested, but MOPAR was. These specific carburetors were then modified and converted from vacuum secondary to full mechanical in the form of Holley List 4782/4783s which MOPAR offered for competition uses thereafter."

Tom V.
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Last edited by Tom Vaught; 12-18-2017 at 09:14 AM.
  #100  
Old 12-18-2017, 03:19 PM
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A bit more today on Holley Carbs.

Mike Urich might have "Written the Book" (books actually) on Holley Carbs but Mike was an Holley Executive Engineer and had time for that kind of thing plus it was good for Holley.

One of the best Holley Engineers (Carb Men) I ever worked with was CHUCK GULLEDGE.
Chuck left Holley, some years after I did, moved to Clearwater, Florida, and opened up CHUCK GULLEDGE Fuel Systems. He mostly built Pro Stock Dominator Carbs for Racers.

I heard about a Dyno Test, run years ago on a Pro Stock Truck engine that was on the dyno.
The carbs were a pair of Holley Dominators built by a company in the northern midwest. Will not go any farther on that deal by providing a name.

So they run the Midwest carbs and they get a number and call me up. I say, what is the deal/
Dyno Owner says, "Tom, the engine seems down on power. I thought it would make more."

So I said" Got any OTHER carbs laying around that you could borrow for the Dyno Test? Braswell, etc? So he says, nope, don'e have any of david's stuff but have tested it in the past and it is good stuff. If I don't try some other carbs the engine will be off the dyno the day after tomorrow."

Then he says, "Hold one, I remebber a older set of carbs under a bench from years ago in some Holley Boxes. Came with the shop when I bought it."
So he looks around and finds the Dominators in the Holley Boxes and pulls one out and sees the Chuck Gulledge tag on the thing. Says "ever heard of that guy?" This is right after Chuck left Holley. So I tell him, blow the carbs off, change the bowl gaskets and bolt them on the engine.
DO NOT TOUCH THEM OTHERWISE.

So he does that, bolts them on the engine and runs a few tests. Calls me back.

Says: Tom, those carbs right out of the boxes were 38 HP better vs the other carbs. I ran the testing several times because I could not believe the numbers and even swapped the other carbs back on and lost the HP I gained from the under the bench carbs.

So I said, you want to make the customer happy, sell him those Gulledge carbs, tell him don't touch the carbs except for gasket changes, and tell him to sell the other carbs he bought to the fastest guy he races against.

Do not know if he did all of that but that truck was kicking butt in that class the rest of the season.

So Mr Chuck Gulledge, not only was a Holley Engineer but also a Top Notch Carb Builder.
You ever find some of his stuff BUY IT! Sometimes who builds the carb(s) can really make a difference and there are GOOD Builders and GREAT Builders
if you catch my drift.

Tom Vaught

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