Author Topic: TRACO Fans  (Read 124255 times)

Coloradoamx

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Re: TRACO Fans
« Reply #195 on: November 15, 2018, 02:27:58 AM »
I finally took the plunge and relocated the dry sump tank to it's proper place.  I had it mounted inside the car, but the original SCCA rules required that it was to be "forward of the firewall."  This is the place the original Penske car had had the tank located. 



Jon Mello

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Re: TRACO Fans
« Reply #198 on: November 21, 2018, 01:23:44 AM »
Thanks for posting.  Those are really neat.
Jon Mello
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PHAT69AMX

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Re: TRACO Fans
« Reply #199 on: July 07, 2019, 07:31:02 PM »
Hope not to "junk up" this thread, but it is where Jon Mello graciously posted on
page 9, reply #131, pictures of a brand new Holley List 4830 GM 3965736 Double Pumper Carburetor.

I am not sure, but from research have come up with a theory why the 4830 "exists".
In most basic terms Holley Carburetors are "grouped" or "sized" by Throttle Valve ( Butterfly ) Diameters.
1-9/16" Dia, 1-11/16" Dia, & 1-3/4" Dia, are the 3 "Basic" Square Flange Performance Carb "families".
GM / Chevrolet 1st had Holley Double Pumper Carbs with 1-9/16" & 1-3/4" Throttle Valves
and this left a "vacancy" at the 1-11/16" Diameter Double Pumper Level, which the List 4830 filled.
That's my theory / "discovery", what I wanted to share for your review, comment(s).
Information found in the 1971 GM Chevrolet Special Equipment Catalog fueled (ha!) this opinion.

At the top of catalog page 8 is a brief Carburetor "Summary Chart" showing 3 Double Pumper Carbs:

1-9/16" Dia. 585-600 CFM Double Pumper List 4295 # 3957859 - '68 Xram 2nd Design
1-11/16" Dia. 830 CFM Double Pumper List 4830  # 3965736 - ? not used as OEM ?
1-3/4" Dia. 850 CFM Double Pumper List 4296 # 3955205 - L88 & ZL-1

As previously posted elsewhere, in the Trans Am Camaro Section, research and conversations
suggest that the very 1st Double Pumper Holley was the 2nd Design 302 List 4295 585 CFM DP
and / or, or maybe at the same time, the L88 2nd Design List 4296 850 CFM DP.
Then the List 4830 830 CFM DP was procured / produced to "fill the 1-11/16" Gap"...

GM and Chevrolet appear to have been 1st to conceive, procure, and use Double Pumpers in late '67 & '68.

The "universal" Series of Holley Double Pumper Carburetors from 600 to 850 CFM we all know as the
4776, 4777, 4778, 4779, 4780, 4781 were introduced in 1969 per a '69 Shelby Catalog, AFTER the GM ones !

The "mid-sized" List 4830 1-11/16" Dia Throttle Plate is used in ALL of those, except the smallest and largest.
And the smallest, 1-9/16" 600 4295, and the largest, 1-3/4" 850 4296, Chevy developed and had 1st !

Interested in others opinions, if any, Thank You.

PHAT69AMX

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Re: TRACO Fans
« Reply #200 on: November 17, 2019, 11:29:51 PM »
? AMC Traco Holley 780 Center Squirter Carburetor ?

? AMC used / had, and Traco was envolved ?...

A Holley 780 CFM Center Squirter ( Centra-Flow ), unknown Holley List Number Carburetor?
When 1st introduced in maybe late 1968, intro Advert in Feb '69 Hot Rod Mag,
the Center Squirter was 1st called 'Centra-Flow' and/or '4-Shooter'...
ONLY 2 were 'made', List 4224 at 660 CFM, 4x 1-11/16" Butterflies
and the monster hog short lived List 4223 850 CFM with 4x 1-3/4" Butterflies.
afaik there never was any 780 CFM Center Squirter.
BUT there it is in this on page in pics and text in this
'Complete Book Of Engines' Traco AMC Trans Am engine article, 'Presenting The AMC Show' .
AND it was or appears to be an 'unknown' or 'undocumented' version possibly...

Sources / Reasoning.

A vintage Hot Rod mag I think publication 'Complete Book Of Engines'
text and pictures... some info, lacking specifics.
and
FIA SCCA Trans Am Homologation Papers and on-hand AMC period documents.

Trans Am Rules dictated / specified ONLY Carburetor Butterfly Diameter & quantity !
Nothing more, No List Number, AMC #, Venturi Size...
So....

Must be 4x 1-11/16" Butterflies to meet SCCA Trans Am Rules
and I think what Traco did or had done, was, maybe,
they used a List 4223 850 Venturi sized main body
which had 4x 1-9/16 Dia Venturis with 4x 1-3/4 Butterflies
with a TransAm rules dictated 1-11/16 Butterfly Plate from the List 4224 660
to make this 'bootleg' 780 CFM Center Squirter in that 'Complete Engines Book' article !
Must have worked, but had almost NO venturi 'shape' !
4x 1-9/16 Venturi Diameters and 4x 1-3/4 Butterfly Diameters !
so almost no TAPER / Venturi shape created going from 1-9/16 venturi to 1-11/16 'Flies !
But maximum air flow potential AND meets SCCA 1-11/16 'flies rules..
And, in other 'series' with different rules, like IHRA, USRA, or just street / hot rods
I think most likely to have be used might have been the then brand new
but short lived Holley List 4223 850 Center Squirter / Centra-Flow 4-shooter
newly introduced not before seen or previously existed before mid to late '68, early '69.

Might anyone have, or know someone who does, that 'Complete Engines Book' ?
A more legible image of the PICTURES in that would be very helpful.


manta22

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Re: TRACO Fans
« Reply #201 on: October 17, 2020, 10:56:35 PM »
I know this is an old thread but I thought there may be some forum members that remember a bit of TRACO history.

I have been told that the engine in a car I own was built by TRACO. The car is a factory-built Mirage that was the showroom demonstrator at Manta Cars in Costa Mesa, CA. They later moved to Santa Ana. The company was owned by two brothers, Brad & Tim LoVette and sold kit cars. Supposedly the 350 Chevy was built by TRACO for the street. It has 186 heads- perhaps modified (I have not torn down the engine yet), a non-stock hydraulic cam, and a Z28 intake manifold.

Does anyone remember TRACO building an engine for Manta Cars around 1976?

Thanks, Neil  Tucson, AZ