#21  
Old 03-01-2020, 06:08 PM
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I have no desire to get into a Copyright War with GM Attorneys, Delphi Attorneys, etc.

I might see if I could get a Disclosure Agreement with the GM Attorneys, Rochester/Delphi Attorneys to post the information.
But that would be down the road or not at all.

Tom V.

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Old 03-01-2020, 07:11 PM
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For those who have not seen a calibration sheet, information on a specific 4-barrel used on a 421 engine.

Idle circuit:

Jet 0.038
Bypass 0.0595
Economiser 0.055
Bleed 0.0492
Port 0.200 x 0.030

Similar figures were also given for the primary metering circuit, the secondary metering circuit, and the pump circuit.

The bill-of-materials simply gives part numbers for the cluster, the jets/metering rods, and the pump/jet with no dimensions.

Jon.

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Old 03-01-2020, 07:41 PM
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Agree, Jon, what you posted is a specific idle calibration circuit for a given carburetor part Number.

Tom V.

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Old 03-01-2020, 08:05 PM
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Schurkey,
Those are what they used to refer to as “Line Manuals”

They have general info such as you give a carb number and they list the jets, metering rods, power piston spring, secondary rods, and any other ancillary numbers such as choke pull off numbers etc.

They do list baseplate numbers, main body numbers, Venturi cluster numbers etc, but no calibration info as was stated above earlier.

  #25  
Old 03-01-2020, 09:14 PM
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Jon Hardgrove created the manifold/carb part number document--I've had it for 35 years or more. It should help people who need info on which manifold is for which year. The carb numbers will help only if the carbs have tags on them, and, even then, there's no assurance that they are the correct tags for the carb they're on. What matters for "correctness" is the casting numbers, which I explain below.

The second document is an exploded view of a '64 Pontiac Tripower with vacuum linkage. Note that the '65 center carb lever extension for mechanical linkage is shown on the bottom right of the page.

I find it interesting that there were only two years where the Tripower intakes had the same casting number--1961 and 1962. Even with the same casting number, some '62's were different in that they had a cast area to install PCV nipples for an "F" fitting.

Also note that the airhorn used on the end carbs is the same casting from 1959 to 1966, casting number 7013206. The float bowls were the same from 1959 to 1963 with casting number 7011997 and from 1964 to 1966 with casting number 7029683. They have slight differences in appearance, but are functionally identical. The 1959 to 1963 throttle bases limited the throttle opening to about 80%, due to the way the throttle stop was machined, whereas the 1964 to 1966 bases allowed full throttle opening. There was a new casting number for the throttle bases sometime in 1966, but I can't see any difference between it and the earlier bases.

I hope this helps you identify parts when you're building a Tripower.
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  #26  
Old 03-02-2020, 06:25 PM
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For many years, I never looked at the Spec Cards that closely because the information I was after was for the 1964 Tri-Power System I had. I checked the carbs on the 1965 GTO but did not look closely at the calibrations.

On that page, the people at Rochester Products used a Black "Magic Marker" to cover over the typed statement at the top of the page. I looked at all the documents today and see that the other sheets clearly state:
"THIS SPECIFICATION CARD IS RESTRICTED TO RPD PERSONAL ONLY"
I found a "Cover Letter" from the same people addressed to me, dated March 5, 1985, that gives ME access to the information for use in restoring the 1965 Tri-Power GTO in the Henry Ford Museum. It does not, obviously, say that I am allowed to pass on this same information to others, even 35 years later.

So thinks Jon for getting me to look much closer at the info they sent me.

Looks to me though that the 389 carbs for all 3 years had similar calibrations for ALL of the 49 state vehicles of a given trans type.
The California Vehicles has a very small difference in some cases and that was on UNIQUE Carb Part Number units built with the California required components.

Same trend applies for all of the 421 engines but did not see any 421 California Tri-Power Carb Sheets.

Tom V.

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  #27  
Old 03-04-2020, 01:32 AM
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Off the subject...

In all your fact finding information. Do you have much info about the tri power setups that had the single base plate for all 3 carbs? Might be a subject for another thread. I remember Mr McLeller’s OHC cam 421 that WAS in his Gran Prix, had such a carb...

I also read somewhere that Pontiac May have been thinking about trying to use such a unit in 67 to get by with the “One” cab rule.
Thanks for your efforts!!!

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  #28  
Old 03-04-2020, 10:35 AM
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The Intake and single carb base for the Tri-Power system you mention, was actually designed by "Mac" and his team several years earlier for his Cammer Engines".

So the "Single Base" system actually "pre-dates" the mentioned "GM Management "One Carb" rule for Pontiac. And yet, the Chevrolet Guys were allowed to continue to offer the HOLLEY "Tri-Power" on that vehicle.

Someone could very well have said, how about we make a single base "Tri-Power" system like "Mac" did on the "Cammers" but that suggestion probably was swept under the rug quickly. Rochester was gearing up for the Quadrajet Carbs for production and would not want that distraction. They were actually getting rid of Tri-power castings, using 64 and 65 end carb parts on 66 systems.

Tom V.


.
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  #29  
Old 03-04-2020, 12:29 PM
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Back on the "Calibration" Holes for the Pontiac Tri-Power Carbs.

My opinion after doing the Holley Sticky and having to post a lot of information on what each of the carbs settings did on the Holley Basic Carb: Throttle Plate Position, Transfer Slot Position, Accelerator Pump adjustments, Pump Squirter Sizes, Float Level and Drop settings, jetting, Primary vs Secondary Air Bleed adjustments, etc when you get to the Pontiac Tri-Power stuff, the End Carb calibration is basically the Carb Jetting.

That is unless you are trying to modify Non Tri-Power Rochester 2 BBL Clusters to act like Tri-Power Clusters. Dick B and a couple of other carb Guys already know how to do those mods and have posted info on what they did. The Carb Clone deal I will not go into.

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  #30  
Old 03-07-2020, 03:01 PM
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Quote:
Originally Posted by carbking View Post
In todays world on the internet, copyrights almost seem anachronistic, but corporate attorneys have no sense of humor, and forgiveness is not in their DNA.

For those that may be unaware, copyrights extend for 75 years, and may be renewed by the copyright holder.

Jon.
Law also provides a provision for "Fair Use" of copyright material.

Fair Use of Copyrighted Material

Fair use is the right to use a copyrighted work under certain conditions without permission of the copyright owner. The doctrine helps prevent a rigid application of copyright law that would stifle the very creativity the law is designed to foster.

The fair use defense is now codified in Section 107 of the Copyright Act. The statutory formulation is intended to carry forward the fair use doctrine long recognized by the courts. The statute provides that fair use of a work “for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use, scholarship, or research)” is not an infringement of copyright.

One important consideration is whether the use in question advances a socially beneficial activity like those listed in the statute: criticism, comment, news reporting, teaching, scholarship, or research. Other important considerations are whether the use is commercial or noncommercial and whether the use is “transformative.” Noncommercial use is more likely to be deemed fair use than commercial use.

I think you're covered by the Fair Use Clause.

  #31  
Old 03-07-2020, 03:21 PM
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Quote:
Originally Posted by PontiacJim1959 View Post
Law also provides a provision for "Fair Use" of copyright material.

Fair Use of Copyrighted Material

Fair use is the right to use a copyrighted work under certain conditions without permission of the copyright owner. The doctrine helps prevent a rigid application of copyright law that would stifle the very creativity the law is designed to foster.

The fair use defense is now codified in Section 107 of the Copyright Act. The statutory formulation is intended to carry forward the fair use doctrine long recognized by the courts. The statute provides that fair use of a work “for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use, scholarship, or research)” is not an infringement of copyright.

One important consideration is whether the use in question advances a socially beneficial activity like those listed in the statute: criticism, comment, news reporting, teaching, scholarship, or research. Other important considerations are whether the use is commercial or noncommercial and whether the use is “transformative.” Noncommercial use is more likely to be deemed fair use than commercial use.

I think you're covered by the Fair Use Clause.
My intent is: Not to make money off the TEACHING/ "Passing On" of Historical Information.

If the Information, Sent to me legally by Rochester Products, (to allow me to configure a Historical vehicle for the Henry Ford Museum to make it correct) then based off of the Fair Use Statute of the law I would assume that means I could Teach other people in the Pontiac Tri-Power Community how to identify
if they have a properly calibrated set of carburetors on their vehicle.

That was the intent, just like in the Holley Thread.

Tom V.

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  #32  
Old 03-07-2020, 03:27 PM
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The 1966 Pontiac Tri-Power Carburetors information, as requested.
(For verification of the Carburetor Calibrations that you have on your 1966 Engines.

"A request has been made to start with the 1966 Tri-Power information, so here it is,
beginning with the Carburetor Part Numbers. Similar info has been posted in bits and pieces in the past so this is a attempt to consolidate some of the information.

1966 389 engines:

Front Carb: 7024178
Front Carb: 7025178

Center A/T Carb: 7026074
Center M/T Carb: 7026075
Center M/T Carb: 7036175* * is A.I.R. Carb - AIR INJECTION REACTOR Carb (Calif.)

Rear Carb: 7024179
Rear Carb: 7025179

1966 421 engines:

Front Carb: 7024078
Front Carb: 7025078

Center A/T Carb: 7026074
Center M/T Carb: 7026075

Rear Carb: 7024079
Rear Carb: 7025079

1) The part numbers for the Rear End Carbs vs the Front End Carbs is 1 number higher.

2) For 1966, the 1966 Tri-Power Carbs basically used the same castings as the 1964 and 1965 castings
as Rochester Products knew that the Pontiac Tri-Power Carb Systems were being discontinued."

I will start with the Front Carb: 7024178 I will follow the same format at the Rochester Products People in the way the
information is presented.

Air Horn Number: 7013884 (1)
Venting: Internal 3/16" dia in scoop
External Venting: None
Support: None
Needle Seat: 7027846 Size: .086:
Float Valve: 7022782 Pull Clip: None
Float Assembly: 7012028 Spring: None
Fuel Level: .750" at 6.0 psi
Mech. Setting: .640" Drop: 1.97"
(to sharp edge of seam at toe of float)
Pump Assem: 7020584 (synthetic)
RET Spring: 7004597 Size: .025"
DUR Spring: 7011385 Size: .045"
Pump Rod: 7013276 Length 2-3/4"
Pump Jet: drill (2) Size: .030"
Jet Location: In Cluster
CAP cc/10 strokes: 15.0 - 18.0
Rod Set: .600 from air cleaner flange surface to top of pump rod
Power Piston Assy: None
act spring (blank) Oz Color (blank)
Power Valve Assy: None
Power Rest: None Size: (blank)
Metering Rod: (blank) Spring: (blank)
Rod Size, Power (blank) Econ: (blank)
Cut-In down at: (blank) "Up" at: (blank)

MM. Jets: 390 cc, 60 degree, 7008668 "C"

Choke Housing: None (The next 14 lines available for the Choke Description are blank)

Float Bowl (Finish) Float Bowl and Body Number: 7013258
Venturi Size: 1-5/16"
Cluster: 7016687 Boost Size: 1/8
Nozzle: 7015151 rel zero
Idle Tube: None Size: (blank)
Channel Rest: None Size: (blank)
Hi-Speed Bleed: drill (2) Size: .034
L.I.A.B: None
Idle Bleed: None
Top Bleed: None
Side Bleed: None
Insert: (2) 7008866 (trumpet)
Radial Tubes: (blank) Size: (blank)
Crossover Chan: None Main Well Chan: None

Throttle Body Assem: 7027776 (2*)
Body & Bowl Assem: (blank)
Thr Body No: 7013262 Bore: 1-11/16
Thr Valve: 7027791 Angle 15 degrees
Idle Needle: None
Idle Needle Orifice:
All drilling info is blank

I will finish the document later

Tom Vaught

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Last edited by Tom Vaught; 03-07-2020 at 04:17 PM.
  #33  
Old 03-07-2020, 06:23 PM
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Quote:
Originally Posted by Tom Vaught View Post
The 1966 Pontiac Tri-Power Carburetors information, as requested.
(For verification of the Carburetor Calibrations that you have on your 1966 Engines.

"A request has been made to start with the 1966 Tri-Power information, so here it is,
beginning with the Carburetor Part Numbers. Similar info has been posted in bits and pieces in the past so this is a attempt to consolidate some of the information.

1966 389 engines:

Front Carb: 7024178
Front Carb: 7025178

Center A/T Carb: 7026074
Center M/T Carb: 7026075
Center M/T Carb: 7036175* * is A.I.R. Carb - AIR INJECTION REACTOR Carb (Calif.)

Rear Carb: 7024179
Rear Carb: 7025179

1966 421 engines:

Front Carb: 7024078
Front Carb: 7025078

Center A/T Carb: 7026074
Center M/T Carb: 7026075

Rear Carb: 7024079
Rear Carb: 7025079

1) The part numbers for the Rear End Carbs vs the Front End Carbs is 1 number higher.

2) For 1966, the 1966 Tri-Power Carbs basically used the same castings as the 1964 and 1965 castings
as Rochester Products knew that the Pontiac Tri-Power Carb Systems were being discontinued."

I will start with the Front Carb: 7024178 I will follow the same format at the Rochester Products People in the way the
information is presented.

Air Horn Number: 7013884 (1)
Venting: Internal 3/16" dia in scoop
External Venting: None
Support: None
Needle Seat: 7027846 Size: .086:
Float Valve: 7022782 Pull Clip: None
Float Assembly: 7012028 Spring: None
Fuel Level: .750" at 6.0 psi
Mech. Setting: .640" Drop: 1.97"
(to sharp edge of seam at toe of float)
Pump Assem: 7020584 (synthetic)
RET Spring: 7004597 Size: .025"
DUR Spring: 7011385 Size: .045"
Pump Rod: 7013276 Length 2-3/4"
Pump Jet: drill (2) Size: .030"
Jet Location: In Cluster
CAP cc/10 strokes: 15.0 - 18.0
Rod Set: .600 from air cleaner flange surface to top of pump rod
Power Piston Assy: None
act spring (blank) Oz Color (blank)
Power Valve Assy: None
Power Rest: None Size: (blank)
Metering Rod: (blank) Spring: (blank)
Rod Size, Power (blank) Econ: (blank)
Cut-In down at: (blank) "Up" at: (blank)

MM. Jets: 390 cc, 60 degree, 7008668 "C"

Choke Housing: None (The next 14 lines available for the Choke Description are blank)

Float Bowl (Finish) Float Bowl and Body Number: 7013258
Venturi Size: 1-5/16"
Cluster: 7016687 Boost Size: 1/8
Nozzle: 7015151 rel zero
Idle Tube: None Size: (blank)
Channel Rest: None Size: (blank)
Hi-Speed Bleed: drill (2) Size: .034
L.I.A.B: None
Idle Bleed: None
Top Bleed: None
Side Bleed: None
Insert: (2) 7008866 (trumpet)
Radial Tubes: (blank) Size: (blank)
Crossover Chan: None Main Well Chan: None

Throttle Body Assem: 7027776 (2*)
Body & Bowl Assem: (blank)
Thr Body No: 7013262 Bore: 1-11/16
Thr Valve: 7027791 Angle 15 degrees
Idle Needle: None
Idle Needle Orifice:
All drilling info is blank

I will finish the document later

Tom Vaught
So here is the last part of the document (mostly just final Info)
Other: 7013264 thr shaft & lever assy
7015106 throttle body gasket

thr shaft offset .027 - .033

no spark port info

Test Specification 7022221

Min Air .95/ lbs min max
Box Balance 18" Hg - 3" Hg
(Note all 2 BBL carbs are tested at 3" of mercury (TV)

Remarks: (1*) 7013249 needle seat screen
7013250 pump shaft & lever assy cast baffle in air horn 7021007 air horn

(2*) 7013783 throttle lever return spring "dag" treatment on throttle valves.
throttle valves in vertical position at wot.

(3*) 7024953 pump squirter deflector installed over cluster

date 9-3-1963
Customer 1964 2G Pontiac 389 cu in A/T & Syn (Front)
Pow. Pak for Pow Pak assys 7024172 & 7024174
Model 7024178 Similar to 7024078

Tom V.

If you copy the info in a Excel or Word Spreadsheet you can combine the info on one page.

This is the info for the Front Carb on a 1966 Tri-Power System from Rochester Products.
Basically, they gave you part numbers and "additions to the basic 2 G carb as well as Flow Test set points.
No different from what Holley did years ago. No magic here.




Spec No 1 (as released)

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  #34  
Old 03-07-2020, 09:20 PM
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Info on the 1966 Rear Carb Calibration: 7024179

The 1966 Pontiac Tri-Power Carburetors information, as requested.
(For verification of the Carburetor Calibrations that you have on your 1966 Engines.

I will post the Rear Carb: 7024179 info now. Same format, again, from the Rochester Products People
in the way the information is presented by them.

Air Horn Number: 7013885 (1)
Venting: Internal 3/16" dia in scoop
External Venting: None
Support: None
Needle Seat: 7027846 Size: .086:
Float Valve: 7022782 Pull Clip: None
Float Assembly: 7012028 Spring: None
Fuel Level: .720" at 6.0 psi
Mech. Setting: .640" Drop: 1.97"
(to sharp edge of seam at toe of float)
Pump Assem: 7020584 (synthetic)
RET Spring: 7004597 Size: .025"
DUR Spring: 7011385 Size: .045"
Pump Rod: 7013276 Length 2-3/4"
Pump Jet: drill (2) Size: .030"
Jet Location: In Cluster
CAP cc/10 strokes: 15.0 - 18.0
Rod Set: .600 from air cleaner flange surface to top of pump rod
Power Piston Assy: None
act spring (blank) Oz Color (blank)
Power Valve Assy: None
Power Rest: None Size: (blank)
Metering Rod: (blank) Spring: (blank)
Rod Size, Power (blank) Econ: (blank)
Cut-In down at: (blank) "Up" at: (blank)

MM. Jets: 390 cc, 60 degree, 7008668 "C"

Choke Housing: None (The next 14 lines available for the Choke Description are blank)

Float Bowl (Finish) Float Bowl and Body Number: 7013258
Venturi Size: 1-5/16"
Cluster: 7016687 Boost Size: 1/8
Nozzle: 7015151 rel zero
Idle Tube: None Size: (blank)
Channel Rest: None Size: (blank)
Hi-Speed Bleed: drill (2) Size: .034
L.I.A.B: None
Idle Bleed: None
Top Bleed: None
Side Bleed: None
Insert: (2) 7008866 (trumpet)
Radial Tubes: (blank) Size: (blank)
Crossover Chan: None Main Well Chan: None

Throttle Body Assem: 7027768 (2*)
Body & Bowl Assem: (blank)
Thr Body No: 7025611 Bore: 1-11/16
Thr Valve: 7027791 Angle 15 degrees
Idle Needle: None
Idle Needle Orifice:
All drilling info is blank

So here is the last part of the document (mostly just final Info)
Other: 7013264 thr shaft & lever assy
7015106 throttle body gasket

thr shaft offset .027 - .033

no spark port info

Test Specification 7022221

Min Air .95/ lbs min max
Box Balance 18" Hg - 3" Hg
(Note all 2 BBL carbs are tested at 3" of mercury (TV)

Remarks: (1*) 7013249 needle seat screen
7013250 pump shaft & lever assy cast baffle in air horn 7021007 air horn

(2*) 7013783 throttle lever return spring "dag" treatment on throttle valves.
throttle valves in vertical position at wot.

(3*) 7024953 pump squirter deflector installed over cluster

date 9-3-1963
Customer 1964 2G Pontiac 389 cu in A/T & Syn (Front)
Pow. Pak for Pow Pak assys 7024172 & 7024174
Model 7024179 Similar to 7024079

IT IS INTERESTING THAT THERE IS NO MENTION OF THE MECHANICAL LINKAGE TRI-POWER PARTS ON THIS 1966 APPLICATION


Tom V.

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  #35  
Old 03-08-2020, 05:08 AM
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Thank´s for sharing you info Tom V!
In Delco Rochester Bulletin 9C-640 Date December, 1965 #7015106 throttle body gasket (vented) is used for the outer carbs as well as the center cab.
But, in Delco Rochester Bulletin 9C-627 Date May, 1967 (Replaces 9C-640, April, 1966) throttle body gasket #7015345 (not vented) is used.

I have found my 1966 Tripower GTO starts easier hot with the vented 7015106 gasket, but i´m currently using the closed throttle body gasket per the manual.
What was the reason for the change over to the closed gasket?

And, i have not found info for the direct reason on the .030" drilled holes in 1964-66 outer carbs throttle blades, other than keeping the throttle bore clean from "gumming up"?

Looking forward for your info on the center carbs!

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  #36  
Old 03-08-2020, 09:58 AM
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Quote:
Originally Posted by Kenth View Post
Thank´s for sharing you info Tom V!
In Delco Rochester Bulletin 9C-640 Date December, 1965 #7015106 throttle body gasket (vented) is used for the outer carbs as well as the center cab.
But, in Delco Rochester Bulletin 9C-627 Date May, 1967 (Replaces 9C-640, April, 1966) throttle body gasket #7015345 (not vented) is used.

I have found my 1966 Tripower GTO starts easier hot with the vented 7015106 gasket, but i´m currently using the closed throttle body gasket per the manual.
What was the reason for the change over to the closed gasket?

And, i have not found info for the direct reason on the .030" drilled holes in 1964-66 outer carbs throttle blades, other than keeping the throttle bore clean from "gumming up"?

Looking forward for your info on the center carbs!
1) The "Vented Gasket" works well in warmer climates as when you shut off the engine fresh air fromt the vented gasket has a "Fireplace/Chimney" effect that lets fresh air come into the center venturi section of the carb, pass upward to the air filter, and then disperse thru the air filter to the engine compartment when the engine is shut off after running. Heat and vapors rise.

With the California Emissions Standards, back in the early 60s, the California Carbs went to the closed crankcase system which basically trapped the fumes from the carbs until a restart and then the fumes were burned. The PCV system also allowed burning off the crankcase fumes. Later they used Carbon canisters to trap the excess fumes.

2) Most times when you add a bleed hole in a throttle blade you are adding a place for additional idle air to get into the carb with the throttle blades in the correct relationship to the transfer holes or the transfer slots.
Sometimes you do this is the engine has a larger camshaft and needs more airflow to idle with the extra charge contamination from the extra overlap.

If you just crank up the throttle blade then you screw up the primary blade/ or carb idle function. 4 tiny .030" holes can add a bit more idle air flow even with the throttle blades 'Dagged" so no leakage around the blades.

I personally think they did it because they "dagged" the blades.

Tom V.

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Old 03-08-2020, 10:47 AM
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That being said, on the rising fumes, if you have a nozzle drip due to a incorrect fuel level in the bowl then the drops of fuel hit the blades. The fumes, then, sometimes exit the same vented cut-outs in the carb gasket.

Tom V.

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  #38  
Old 03-08-2020, 11:23 AM
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Kenth - none of the Rochester material I have gives a reason for changing from the vented gaskets to the solid gaskets on the outer carbs.

I will hazzard a guess!

Since the reason for the vented gaskets was to alleviate throttle area pressure blowing additional fuel into the intake past the slightly open throttle plates during hot idle conditions; if one looks at the outer carbs, the throttle plates are tightly closed at idle and off idle. Therefore, there would be no benefit in using the vented gaskets on the outer carbs.

If you remember, you corrected me on these gaskets in these forums a few years ago. I was using the early listing for the bill-of-materials. After our post conversation, I have switched to the solid gaskets on these carbs.

There were never any complaints about using the vented gaskets other than why; to which I then responded with the 1957 Rochester/Pontiac bulletin explaining their use.

Personally, I don't believe there would be any different in driveability with either the vented gaskets or the solid gaskets on the end carbs; but that is conjecture, as all of my GTO's were 1964.

If I still had my 1964, I would convert it back to the single 4-barrel it had originally. I foolishly choose "eye candy" over performance when I converted from the single 4 to the tripower.

Jon.

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  #39  
Old 03-08-2020, 12:20 PM
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CENTER CARB 1966 421 engine

The 1966 Pontiac Tri-Power Carburetors information, as requested.
(For verification of the Carburetor Calibrations that you have on your 1966 Engines.


I will post the Center Carb: 7026074 info now. Same format, again, from the Rochester Products People
in the way the information is presented by them.

Air Horn Number: 7031588 (1)
Venting: Internal 7007199 Vent Tube
External Venting: Idle Vent
Support: None
Needle Seat: 7026305 Size: .120
Float Valve: 7022779 Pull Clip: 7006474
Float Assembly: 7012028 Spring: None
Fuel Level: .625" at 6.0 psi
Mech. Setting: .594" Drop: 1.97"
(to sharp edge of seam at toe of float)
Pump Assem: 7032280 (synthetic)
RET Spring: 7004597 Size: .025"
DUR Spring: 7011385 Size: .045"
Pump Rod: 7025575 Length 3.06"
Pump Jet: drill (2) Size: .026"
Jet Location: In Cluster
CAP cc/10 strokes: 18.0 - 21.0
Rod Set: .952 from air cleaner flange surface to top of pump rod
Power Piston Assy: 7012266
act spring 7012265 Oz 8 Color (green)
Power Valve Assy: 7011989
Power Rest: 7010144 Size: (.044)
Metering Rod: (blank) Spring: (blank)
Rod Size, Power (blank) Econ: (blank)
Cut-In down at: 11 "Up" at: 8 all in at 6" hg

MM. Jets: 299 cc, 60 degree, 7008660 "B"
7013333 Idle Compensator Assy:
(140 degree (+ - 10 F) Opening Temp

Choke Housing: (2*) (Some of the next 14 lines available for the Choke Description are blank)
Here are the ones with Info:
Valve No: 7033443 Angle: 20 degrees
Cam No: 7020541
Choke Link: 7019524 Length: 2.671"
wo Kick: .143 - .183 Second Step: .090 .100
Vacuum Break: 25 degrees + - 1.5 degrees (.168 - .192)

Float Bowl (Finish) Float Bowl and Body Number: 7031576
Venturi Size: 1-3/16"
Cluster: 7032380 (4*) Boost Size: 1/8
Nozzle: 7020753 rel .014 - .026
Idle Tube: 7011030 "C" Size: .030
Channel Rest: 7009437 Size: .045
Hi-Speed Bleed: drill (2) Size: .028
L.I.A.B: None
Idle Bleed: None
Top Bleed: .039 over idle tube
Side Bleed: .033
Insert: (2) 7008866 (trumpet)
Radial Tubes: (blank) Size: (blank)
Crossover Chan: .125 Main Well Chan: None

Throttle Body Assem: 7031595
Body & Bowl Assem: (blank)
Thr Body No: 7031597 Bore: 1-11/16
Thr Valve: 7025509 Angle 10 degrees
Idle Needle: 7029605 angle: 20 degrees

All drilling info is blank

Port Punch Length: .250 Width: .030
Port Punch Loc: .233 Top Valve Top Slot
Other: 7032290 throttle body gasket
7020778 thr shaft lever assy
7024885 throttle lever
.055 dia hole in thr valve
thr shaft offset .017 - .023

no spark port info

Test Specification 7022221

Min Air: .65/ lbs min Idle Air rate: .95 lbs min
Box Balance 18" Hg - 3" Hg
(Note all 2 BBL carbs are tested at 3" of mercury (TV)

Remarks: 7013333 idle comp assy
140 degrees F + - 10 degrees F opening temp

(1*) 7021007 air horn gasket 7031590 nut - fuel inlet bend pump lever tang to open idle vent
with .020 gage between thr valve & bore on side opposite idle needle.
(2*) 7026095 vacuum break control assy 7026098 remote choke coil assy
(3*) Service Pump Setting 1-21/64 + - 1/64 from top of die cast air horn ring to top of pump rod
(4*) .026 dia hole aspirator to main well bleed
Note: 7031598 vacuum switch assy

date 3-9-1966
Customer 1966 2G Pontiac (Auto) 421 engine A/C Center

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  #40  
Old 03-08-2020, 12:23 PM
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I may do the 1966 Manual Center Carb later but the basic info from Rochester and how they reported the information is there.

If I find significant differences between the Manual and Auto carbs I will post it.

Tom V.

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