#301  
Old 03-03-2018, 10:51 PM
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What Power Valves do you have in the carb?

Assume that the RPM is same height or less height vs the Victor, why did you remove the 1" Wilson spacer?

Did you check for proper accelerator pump linkage adjustment on the front and rear bowls?
.015"-.050" extra travel of the pump arm when at WOT. No clearance at Idle rpm.

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  #302  
Old 03-03-2018, 11:34 PM
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How to install a Holley Carburetor

1) Remove the Air Cleaner (Detach and note any vacuum line connections to the Air Cleaner).
Take Pictures if you have a camera in your cell phone

2) Detach the fuel Line(s) and wrap the exposed end(s) with clean lint-free cloth to avoid foreign particle contamination.

3) Disconnect and Tag all vacuum hoses (and their locations on the carburetor) Again a camera is nice for this step along with the Tags.

4) Disconnect and remove any throttle linkage to the carb. If the vehicle has a Auto Trans disconnect the appropriate linkage for that trans.

5) Save any and all special clips, brackets, etc if you are changing to a different model carburetor.

6) Disconnect and remove the Choke Cable (if necessary) or the Choke Heat Pipes. Disconnect the Choke Electrical Wires.

7) Remove and save the Carb Retention Nuts (or other fasteners).

8) Vacuum any dirt or debris from the intake manifold /carb before removing the carb from the engine.

9) Clean the Carb gasket Surface on the baseplate. Clean the Intake manifold surface. Cover the Intake opening with a clean cloth.

10) R&R Carb Gaskets and inspect internal parts of the carb for contamination. Install fresh gaskets and the Fuel Bowl Screws
10a) Prior to installing the Bowls Trim the Orange Fuel Bowl Check Valve Stems to just above the "Nub". Torque the Fuel Bowl Screws to 25-30 INCH Pounds.

11) Check the Accelerator Pump Linkage for proper adjustment. There should be .015-.050" ADDITIONAL travel of the pump at WOT.
There should be NO clearance between the Pump Cam, Pump Arm, or the "Rocker Arm" on the bowl at idle.

12) Remove the cloth over the Intake Manifold, Inspect for any dirt, etc. Install the proper Carb Gasket and tighten the carb nuts to 60 to 80 INCH pounds. Tighten in a criss-cross pattern.

13) Reconnect all vacuum line in their proper location

14) Reconnect all electrical connections in their proper locations.

15) Check Choke Linkage for proper opening and high cam function.

16) Reinstall Fuel Line(s) to the carburetor.

17) Add fuel to carb by either remote fuel pump or by squirting fuel into the bowl vent tubes and verifying fuel level is correct on the fuel bowls.

18) Many Holley carbs have fuel bowls with a different height sight plug on the front carb bowl vs the rear carb bowl.
Rear bowl sight plug is .250" LOWER.

So there are the Proper Holley Steps to Remove/ install a carburetor.

Tom V.

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  #303  
Old 03-04-2018, 04:06 PM
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Quote:
Originally Posted by Tom Vaught View Post
What Power Valves do you have in the carb?

Assume that the RPM is same height or less height vs the Victor, why did you remove the 1" Wilson spacer?

Did you check for proper accelerator pump linkage adjustment on the front and rear bowls?
.015"-.050" extra travel of the pump arm when at WOT. No clearance at Idle rpm.
Wasn't able to use the spacer (wanted to) due to the shaker scoop height/fitment. already using the blocker kit for the rpm manifold.

went thru everything today and cured the backfire, thank you for the assist. the carb came with #84 jets all 4. both power valves are 6.5, when I checked the fwd one it had 2 gaskets installed one smashed and tore thru the other pushed to the side. question: my previous carb did not use a rear power valve, was blocked off after tuning perhaps I should do the same now? not certain what that gains. heres what I have after tuning:
87 fwd 88 rear jets
both pv's 6.5
41 squirter
fwd adj screws 1 1/4 turns out, rear 1 turn
8lbs vacuum at idle
18 degrees initial, 34 degrees total timing

  #304  
Old 03-04-2018, 09:03 PM
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Ifn you have a 88 rear jet with the Power Valve, put in a PV Plug and go up 6 Jet sizes more and see how it runs. 6 sizes normally works on less than Dominator carbs. It will be fine with the PV Plug in the rear. Glad to help.

Tom V.

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  #305  
Old 03-07-2018, 08:07 PM
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I was looking thru some old excel files for different images and ran across this link that shows a "cut-away" of a Holley Power Valve along with some carb tips in general.

It goes into a slight bit of tuning Holley Power Valves, but does acknowledge that the Power Valve might be open with the "wrong spring setting" Power Valve but that would not cause the engine to run rich if the carb were idling.

The only way the Power Valve can supply extra fuel to the engine is if the Carb Boosters are in operation. So the Hot Rod Guys finally got that story right in print.

Jeff Smith also touches on a couple of other carbs so it those carbs and info interest you, read those tips too.

Here is the link:

http://www.hotrod.com/articles/carbs-tips-tricks-cheap/

Tom V.

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  #306  
Old 03-07-2018, 08:41 PM
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I posted this info in a different thread but it is good info for the Holley carb thread too.

The old Holley Blue Pumps were about all you had years ago to use for an Electric Fuel Pump.

You could buy 3 of the Stewart Warner electric pumps and gang them together and get decent flow. They had built in regulators.

The Holley Blue and Red pumps were terrible for sticking the flow vanes in the pump in the recessed position. Basically that means the pump does not flow the fuel properly. If you constantly cleaned them and used them for PURE DRAG RACING THEY WERE OK THOUGH. NOISY SUCKERS. Fuel Pressure Regulator flow was poor. You needed a minimum of two of the Blue Regulators even on a SB Chebby.

Mallory came out with the Mallory 140 pumps and they were good for Drag Racing with the Holley 7/16" control ball regulators. Easy 9 second fuel capability.

Holley Blue Pumps and Blue Regulators are #10 on my list of good fuel pumps (#1 being best). GOOD EFI Pumps being #1

The Mallory 140 stuff being maybe a #5.

Most of the higher HP fuel pumps that followed were Drag Only deals and died if you drove much on the street or trips. The Bosch External EFI pumps being the exception. They could put out 200+ gallons per hour at 75 psi and could flow 300 gallons per hour at a carb test pressure. All were Car Frame mounted from the OEMs so lots of noise unless you had the OEM Vibration Isolation mounting hardware.

If you are running 75 PSI fuel pressures 42 pound rail pressures naturally aspirated and 25 psi boost pressures the Bosch #140 pumps really shine. (140 is the last 3 digits of the part number). Most of the EFI pumps fall off pressure badly at the higher fuel pressure requirements. Lots of flow curves out there showing the performance of the EFI Pumps at higher pressures.

Any 255 liter per hour EFI basic pump: (1 liter is slightly more than a quart 4 quarts to a gallon), means the basic pump will flow 63 gallons of fuel at 43 psi and probably twice that amount at 7 or 8 psi so the Tanks,inc 255 liter per hour pumps make great carb fuel pumps and are CHEAP to buy. OEM durability too. 100,000 mile life. A In-Tank pump system is hard to argue with with today's e-15 and e-85 mixes out there at the pumps. That crap will kill a old style Holley pumps quickly.

Tom V.

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  #307  
Old 03-07-2018, 09:04 PM
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Quote:
Originally Posted by Tom Vaught View Post

The only way the Power Valve can supply extra fuel to the engine is if the Carb Boosters are in operation. So the Hot Rod Guys finally got that story right in print.

Jeff Smith also touches on a couple of other carbs so it those carbs and info interest you, read those tips too.

Here is the link:

http://www.hotrod.com/articles/carbs-tips-tricks-cheap/

Tom V.
Good stuff, but I'd caution people following the "Idle Speed Deeds" section. If you expose too much of the secondary idle transfer slot it can cause other issues.

And rather than permanently drilling holes to compensate for "big cam off-idle stumble," (which is really hard to undo), one should try adding static timing. As a matter of fact, from one of the previous referenced articles where the Holley technician was helping numerous people on the Power Tour, the biggest contributor to driveability issues were people attempting to use the factory or lower static ignition timing with long duration and/or tight LSA cams. Once he fixed that part, then he was able to get the carb dialed in properly.

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Last edited by amcmike; 03-07-2018 at 10:03 PM.
  #308  
Old 03-07-2018, 10:38 PM
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Some engines need a bit of a air bleed hole in the Throttle Plates Plus the Secondary Throttle Blade Position to dial things in.
You are correct, you have to pay attention to all of the details in tuning an engine.

The WW-II Mechanic Instructor who was Chief Mechanic at our Pontiac Dealership (My uncle owned the place) always preached "
Get the Timing right first before you ever monkey withe carburetor."
Delbert Forrest was his name. RIP Del.

Tom V.

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  #309  
Old 03-09-2018, 11:23 PM
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I wanted to post a bit of information about how Holley Transferred the fuel from the Single Inlet Fuel Fill Banjo Fitting to both carb fuel bowls.

1) Fuel comes from the Fuel Pump/fuel filter thru a hose to the Banjo Fitting on the Primary Bowl of the Holley 4160 Carb. Pic #1 Post #310

2) There is a drilling in the fuel bowl close to the Banjo Fitting pointing towards the rear bowl. Pic #1 Post #310


3) There is a second drilling facing the Primary Bowl on the Secondary Bowl. Pic #1 Post #310


4) A aluminum tube with two raised sealing surfaces near the edge of the tube transferred the fuel between the bowls. Pic #2 Post #309


5) In order for the fuel to not leak past the aluminum tube ends a simple o-ring was installed over the tube end and the o-ring lubed up with a touch of vasoline and was inserted in one of the bowls drilled cavity. Pic #3 Post #309

6) A second o-ring using vasoline is installed on the tube and the into the other drilling in the other fuel bowl. It does not matter which one you install first. I work typically on the Primary Bowl components first so the secondary bowl gets installed at the last step.

Here are some pictures of both the old style O-ring transfer tube assy and the New style assy. Pic #4 & 5 Post #309

Tom V.
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Last edited by Tom Vaught; 03-09-2018 at 11:33 PM.
  #310  
Old 03-09-2018, 11:29 PM
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Here is a picture of the 4160 carb showing the Banjo fitting and the transfer Tube parts installed.

Tom V
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  #311  
Old 03-13-2018, 08:48 AM
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Going to talk a bit about Holley Throttle Linkage Levers today.

Knowing how to quickly recognize a Chebby carb from a Ford or Chrysler Carb at the swap meet helps in the Bargaining Process.

It also helps you understand the Positives and Negatives of the linkage.

The first carb we will talk about is a carb you will find a lot of times at the local swap meets. See "Vacuum Linkage" Picture.
It is a "Chevrolet Style Carb" and has Vacuum Secondary Linkage. The linkage that you see on the right side of the picture shows the Positive Closing "Link and Slot" system. When the Primary Lever closes the Primary Throttle Blades it also pulls shut the Secondary Throttle Blades. The link between the two levers makes that happen. A "Vacuum Secondary" Carb

The second linkage shown is again Chevrolet style linkage but designed for a 660 "Center Squirter Carb" or some of the very old 850 cfm Tunnel Ram carb applications. See "Double Hump" Picture.
It is called "Double Hump" Mechanical Linkage because of the visible "double hump" in the slot portion of the Primary Throttle Linkage lever.
The Linkage goes to a given point on the Primary Blades of the Primary Shaft and then opens all of the Throttle Blades quickly from that point until WOT of the carb.

The next picture is an example of the "Single Hump" Tunnel Ram Linkage. As you can see in the "Single Hump" Picture the Primary Throttle Blades can only move a few degrees before the Secondary Blades start to open. A "Race Only" linkage for most people. You can drive a engine on the street with this linkage but gas mileage will be poor as every time you touch the throttle 4 Accelerator Pumps are dumping some fuel into the intake manifold.

In this picture: "Jerry Rig" the "Operator of the Vehicle' has "Jerry Rigged" an factory Chevrolet Style Vacuum Linkage "Throttle Return Linkage" to act like a poor mechanical secondary linkage. Massive hesitation with this set-up on acceleration.
In the Old Days you could buy a Carb Squirter with 4 squirter nozzles (2 extra long tubes extension nozzles added on a regular Primary Shooter).
You drilled a couple of holes in the choke housing, stuck the "extended tube shooters thru the holes" and hoped the accelerator pump fuel went somewhere in the secondary barrels. Without the secondary fuel this carb will have a big secondary throttle hesitation with any throttle movement. Some people used a sheet metal screw part way down the slot that worked much better vs this crappy tie-wrap design.

In the final picture, "Johnson Linkage" you can see the mechanical linkage to open the secondary barrels using a very complicated "Pivot Cam" like a "Center Squirter Cam" uses but turned sideways with the "roller" on the top. Lots of pieces and cost but it was designed by a Holley Carb Chief Engineer so it must have been PERFECT and therefore went into production. $$$$$$ It Works Well though!

So now you have the typical linkage systems you will run across on the carbs you will find at the swap meets.

Tom V.
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Last edited by Tom Vaught; 03-13-2018 at 08:57 AM.
  #312  
Old 03-15-2018, 08:26 AM
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Going to post a few additional Holley 3-BBL pictures today and see if people can recognize the carbs and the differences.

Tom V.

Hints: In the First Picture you can see that the carb is a Holley 3-BBL carb.
You can also see that it has the typical 4 bolt cover for the Secondary Vacuum Diaphragm to open the single Rear Barrel.
You can see that it is a 1050 carb vs a 950 cfm carb because it has "Tube Nozzles" vs "Rear Boosters".
The carb also has the 50cc Accelerator Pump Arm and for sure the 50cc Pump Housing and Diaphragm

Hint: In the second Picture you can see the "Extended "Primary Accelerator Pump "Shooter" Nozzle.
You can also see the "Cable Driven" Choke Plate on the carb and the other parts normally used on a Manual Choke Carb.

Hint: 3rd Picture you can see the 50cc Pump Housing and Diaphragm. The 3-BBL rear Throttle Plate and the Rear Race Bowl without
machining for an Accelerator Pump.

Hint: In the Last Picture you can see the carb is not a 1050 cfm carb but is a 950 cfm carb (4 normal boosters).

What DID I NOT TELL YOU (based on the pics in today's thread?)

Tom V.
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Last edited by Tom Vaught; 03-15-2018 at 08:43 AM.
  #313  
Old 03-15-2018, 11:16 AM
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Ok, if you compare Picture #2 with Picture #4 you will see that the Choke Cable is missing from the Hole that the cable passes thru in the airhorn ring. Not a big deal there.

The thing that is interesting and I have only seen it a few times in Holley Experimental Carburetors is the "Sleeved Carb Venturi Inserts". Two carbs on special 366 cid Ford Tri-Power NASCAR Primary Carb set-ups and this time on the 3 BBL 950 CFM carb in the Picture.

I worked on the special 366 cid Ford Tri-Power NASCAR Primary Carb set-ups and Holley Experimented on the two sets of special 429 Super Cobra Jet Tri-Power Carbs. The 429 carbs were the ones I rebuilt and tuned for the Ford Engineer. Notice the bright aluminum rings in the pictures of the Primary Venturis.

But this is the first time I have seen a picture of the sleeved 3-BBL carb in a internet picture.
(The actual carb cfm on the stock 3-BBL was 950 cfm). With the sleeved insert 780 (3310 venturi) the carb was probably closer to a real 870 cfm carb but with a 3-BBL design. Holley sold a lot of 3-BBLs to Baldwin-Motion on Long Island NY for the Chebbys so this carb could have been a test carb from that effort.

Tom V.

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  #314  
Old 03-15-2018, 11:35 AM
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Quote:
Originally Posted by Tom Vaught View Post
Going to post a few additional Holley 3-BBL pictures today and see if people can recognize the carbs and the differences.

Tom V.

Hints: You can also see that it has the typical 4 bolt cover for the Secondary Vacuum Diaphragm to open the single Rear Barrel.
Just a tip for those that might be rebuilding one of these. These vacuum diaphrams are larger than a typical holley 4-barrel. They happen to be the same size used on the 67-69 tri-power Corvette setup, for those looking for one.

  #315  
Old 03-15-2018, 01:48 PM
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Very True on the size being the same.

If you modify the 6 bolt diaphragm (Corvette and Mopar) by removing the 6 bolt "stem" and swapping on the 3-BBL 4-bolt "stem" then the 6-bolt diaphragm can be made to work with the 3 BBL housing.

The 3-BBL diaphragm has been out of service for many years. It will require a slight change in the stem length (after you grind off the factory peaned end and the stem modified to be re-peaned on the 6 bbl diaphragm), using a lathe).

Tom V.
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  #316  
Old 03-15-2018, 02:14 PM
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Very True on the size being the same.

If you modify the 6 bolt diaphragm (Corvette and Mopar) by removing the 6 bolt "stem" and swapping on the 3-BBL 4-bolt "stem" then the 6-bolt diaphragm can be made to work with the 3 BBL housing.

The 3-BBL diaphragm has been out of service for many years. It will require a slight change in the stem length (after you grind off the factory peaned end and the stem modified to be re-peaned on the 6 bbl diaphragm), using a lathe).

Tom V.
Yep, that's why I mentioned this little tip. I see these carbs at swap meets occasionally, usually fairly reasonable because the owner thinks it isn't serviceable. Cool carburators, thanks for posting that.

  #317  
Old 03-15-2018, 03:21 PM
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Ever see something like this? Looks like someone converted this one to mechanical secondaries. I've never had it apart so I have no idea what jets or power valve it would have. The primary butterfly has "180" stamped on it, LIST 4604-S. I would like to find a correct diaphragm for it.
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Last edited by SRR; 03-15-2018 at 03:38 PM.
  #318  
Old 03-15-2018, 03:27 PM
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Doesn't look like that would work very well, no secondary accelerator pump shot, and when they removed the vacuum secondary diaphragm they just left the vacuum port open.

Some guys back in the day used to shove a screw in the vacuum secondary linkage making it more of a mechanical action and left the vacuum diaphragm in place. Even Dick Harrell mentions doing that on his cars when he was road testing the very first ZL1 built. I don't recommend it but to each his own.

  #319  
Old 03-15-2018, 03:41 PM
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Quote:
Originally Posted by Formulajones View Post
Doesn't look like that would work very well, no secondary accelerator pump shot, and when they removed the vacuum secondary diaphragm they just left the vacuum port open.

Some guys back in the day used to shove a screw in the vacuum secondary linkage making it more of a mechanical action and left the vacuum diaphragm in place. Even Dick Harrell mentions doing that on his cars when he was road testing the very first ZL1 built. I don't recommend it but to each his own.
Unless they jetted the crap out of it. I am concerned because the secondary sits open like that at idle??? Doesn't seem to be a way to adjust it tighter.

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  #320  
Old 03-15-2018, 04:01 PM
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You're right, having it open that far is reason for concern. It will cause quite a few problems, high idle only being one of them.

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