Messages

Old notes show 1115355 = Borg Warner V280P , also VC1765, all brands stamped "B20" on vac adv can mtg flange, vacuum advance starts at 5.0"-7.0" Hg

Wow.... my goodness...

Realize this is an old thread.  Only 1 of 2 threads that a search for "Mallory RevPol" found.

  The Mallory RevPol DoubleLife dual-point distributor is unique?  It only has a 4-Lobe Point Cam.  Each point set fires only 4-times per revolution rather than 8-times, each point-set fires only 4-times each to fire all 8 cylinders.  Is this correct?

  A conventional Dual-Point Distributor has an 8-Lobe Point Cam, both point-sets fire 8-times per revolution, and point overlap overlaps increasing coil saturation.  Is this correct?

  The Mallory RevPol DoubleLife Dual Point 4-Lobe Distributor should be more rpm friendly since the point-sets are cycling at a lower rate?

Could be sanctioning body rules for what is legal for use in a given class of racing, such as NHRA Super Stock.  For a given carb, intake, etc to be legal it must be available on a minimum of 50 cars as factory built from what I understand, at least is was 50 units minimum in 1969.  Then any car could use those pieces and parts and still be legal.  Say a '69 ZL1, a person could build a "clone" and it would still be legal in NHRA Class using all the parts factory installed and sold on the (50) copo cars, even though it was not an actual ZL1.  That might be why the less-street-friendly L78 396 option.

Fits stock AMC heads, Traco was late to the game develping it for AMC for TransAm who then changed the rules back to a single 4-barrel, so the Traco AMC 2x4 Intake was shelved, unknown how few were produced, have info of two known pieces.  One was bought along with and on a used AMX in the 80's maybe not 10 miles from the Traco Culver City CA location, afaik.

Anyone seen this AMC V8 Traco 2x4 Intake Manifold before ?
Guess technically it would not be considered a crossram.

Recently learned, the honorable Mr. William Bill Howell, passed away July 22, 2021

If I understood David Vizard, the leaner the mixture, the slower it burns.  So earlier Vac Adv was on Manifold Vacuum.  The "Emissions" came into play, so the did what they "had to" instaed of "what the engine wanted".  The wanted less HC's out the pipe at idle.  So they opened the carburetor wider at idle to let in more air, more O2, cleaner burn.  But then the idle speed was way to high.  So they came up with PORTED VACUUM on the Vac Adv so that it was NOT deployed at idle, and the further opened carb let in more air and O2, and tailpipe HC's were decresed, but the engines hated it...

A significant consideration is those Edelbrock AMC CrossRam Intake Instructions...
were written and done before the Double Pumper ever had existed yet...
Except for only a few well informed people I'd guess and those who noticed,
as for 3/4's to 2/3rds of 1968 GM was running double pumpers in TransAm & on the L88's, were they not?  And no one else had them, correct ?  They were a brand new idea in 2nd quarter '68, no?
So the above Edelbrock Instructions that talk about using a pair of modified List 1850's or a pair of List 4224 660's... it makes no mention of a pair of little 600 Double Pumpers BECAUSE THEY DID NOT EXIST YET!
Although, almost, kinda, like right at about the exact same time, ? April 1968...
GM developed and issued the 2nd Design 2x4 302 4295 "600 DP" Holley...
A CrossRam just loooooves a pair of small 600 double pumpers don't they?

If watching that doesn't make your hairs stand up then you ain't alive man 

Second attempt for improved image quality, please advice if these are more legible, Peace

AllState Carburetor in New York ?

Better resolution images are too large file size, typed text :

( start page 1 of 2, 1968-9 INSTRUCTION SHEET FOR EDELBROCK STR-11 )

INSTRUCTION SHEET FOR EDELBROCK STR-11
(American Motors engines 290-, 343-, and 390)
AMC part # 2570  install kit # 2571
( ref, SBC STR-10 = part # 2560  & install kit # 2561)
REF - AMC instructions call for Edelbrock 2x4 # 2562 Conversion Kit...
? Does Edelbrock Chevy STR-10 Crossram vintage instructions ?
? ALSO call for the Edelbrock 2x4 # 2562 Conversion Kit ?

Carburetors
-----------

      1. For 290-, 343-, and 390-inch engines (applicable to
         the 390 only where low rpm performance is required),
         we recommend use of the Holley #R-1850-AAS (same as
         1-14) which is rated at 600 cfm.  Conversion Kit
         (Edelbrock cat. no. 2562) includes all necessary
         change-over parts and must be used to prevent car-
         buretor flat-spots at the secondary opening point
         (due to manual opening characteristics).  Secondaries
         must be operated by vacuum, and this conversion kit supplies
         the pieces for this alteration.

         Steps for the conversion are as follows:

             a.  Remove stock vacuum secondaries and automatic
                 choke mechanisms from the sides of the carbu-
                 retors.

             b. If you wish, this is a good time to remove
                both choke butterflies.

             c.  Assemble and install the provided secondary
                 diaphragm unit in the same way the stock pieces
                 were removed.  If there is question concerning the
                 trueness of the diaphragm cover, dress it on a sur-
                 face topped with a sheet of grit paper and plunge
                 the cover in a bath of solvent before blowing it
                 out with air.  Make certain that there are no
                 leaks between the secondary lid and body follow-
                 ing diaphragm installation.  Also make sure
                 to provide a good seal between carb body and
                 diaphragm housing.

             d.  Install #68 primary jets and 0.076-inch drilled
                 secondary plates.

             e.  Set primary floats with a #10 drill bit
                 (0.195-inch o.d.) and secondary floates with
                 a #2 bit (0.220-inch o.d.).  These drill bits
                 are used as gauges by placing them between the
                 float and the float bowl chamber with the chamber
                 inverted.



( end page 1 of 2, 1968-9 INSTRUCTION SHEET FOR EDELBROCK STR-11 )

------

( start page 2 of 2, 1968-9 INSTRUCTION SHEET FOR EDELBROCK STR-11 )



cont'd.

      2.  For 390-inch engines (not required to perform
          in low rpm ranges), use the Holley #S-4224 AAS
          which is rated at 660 cfm.  Stock jetting is
          adequate for initial running and secondary opening
          mechanism should remain manual.  Set float levels
          as per instructions for #R-1850-AAS

Manifold Installation
---------------------

      Installation of the Edelbrock STR-11 is relatively simple.
      You should exercise caution to provide adequate head-to-
      manifold seal, and subsequent mixture contamination when the
      engine is returned to service.  Use new gaskets and seals
      in all areas and make certain that each throttle linkage
      member is free of binds and obstructions.

Fuel Pressure
-------------

      This isavery important part of your manifold/carburetor
      assembly.  We suggest use of two Stewart-Warner fuel pumps
      (S-W #D-240-A) mounted in parallel with two separate fuel
      pickups from the fuel tank.  Use two 1/2-inch (i.d.) neo-
      prene fuel lines connected into a fuel block with two
      3/8-inch (i.d.) neoprene lines joining the carburetors.
      Fuel pressure should be a maximum of 7 psi at engine
      idle) and 5 psi (at top engine speed, in traps, etc.).
      We also recommend the use of a fuel pressure gauge
      mounted to facilitate easy reading at all times.  A lack
      of adequate fuel pressure can lead to a lack of overall
      engine performance.

Air Cleaners
-------------

      For maximum performance from your new Tunnel Ram, we
      suggest use of the #EC-902P air cleaners.  These units
      are designed around use on the STR manifolding and
      normally provide adequate hood clearance.  In situations
      where large amounts of carb-to-hood clearance is avail-
      able, use of other types of cleaners is sometimes
      acceptable.  Additional air cleaner/throttle linkage
      information will be released immediately following avail-
      ability.  This data will be dispensed through your local
      Edelbrock dealer, and we suggest that you contact him in
      the near future if questions arise in your particular
      installation.



( end page 2 of 2, 1968-9 INSTRUCTION SHEET FOR EDELBROCK STR-11 )

---------------------
end of document - 08-03-2020 - CKusTomSS

[1969-ish EDELBROCK # 2560 STR-10 SB Chevrolet Crossram Intake Manifold Instructions]

Hello, hope everyone is having a Wonderful 2021 Labor Day Weekend!
Thought no harm asking if anyone might have and be willing to share images of vintage original
1969-ish EDELBROCK # 2560 STR-10 SB Chevrolet Crossram Intake Manifold Instructions

These are images of 1969-ish EDELBROCK # 2570 STR-11 AMC Crossram Intake Manifold Instructions.

Very very curious just what the Edelbrock Chevrolet Instructions might have to say.

It would be greatly appreciated if someone happens to have and shares the SBC Edelbrock Instructions Version.

Peace.

[List 4210]

May I ask, who if anyone, that may have on-hand a Holley List 4210 Carburetor and/or a Holley List 4295 Carburetor, both GM original Z28 302 Crossram Conversion Kit # 3940077 Kit carbs, 1st Design & 2nd Design, and might be so kind, willing, & generous to MEASURE, Pin Gauge, all the FIXED ORIFICE SIZES found in those 2 Carburetors, record, document, and SHARE that critical specific detailed dimensional information so that it is captured and not lost to history   No where known does that all important functional information exist, and it would be a wise & prudent thing to capture it, would it not ?  Here are "Blank Forms" to record the dimensional values on, then scan, post, & share, addition of the unlabeled Emulsion Bleeds & Kill Bleed, if present, should be added to the "Form" actually.  Thank You, Hope all is well with you and yours.  Peace