Author Topic: W72 quadrajet cast number?  (Read 1135 times)

airpirate

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W72 quadrajet cast number?
« on: April 26, 2017, 07:30:12 PM »
I have a 78 with the W72 performance option, I am having the carb rebuilt and need the vast number . Just curious if anyone would know that before I brave the snow and cold to check

Thanks



78 TA 6.6 W72 WS6
10 Land Rover
08 Dodge Ram
15 Ford Edge
03 Indian Motorcycle

jonathonar89

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Re: W72 quadrajet cast number?
« Reply #1 on: April 26, 2017, 08:06:09 PM »
17058263 I believe...17059263 for '79

airpirate

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Re: W72 quadrajet cast number?
« Reply #2 on: April 26, 2017, 08:27:38 PM »
Thanks partner!  Appreciate the help



78 TA 6.6 W72 WS6
10 Land Rover
08 Dodge Ram
15 Ford Edge
03 Indian Motorcycle

jonathonar89

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Re: W72 quadrajet cast number?
« Reply #3 on: April 26, 2017, 09:02:48 PM »
Thanks partner!  Appreciate the help

That was straight from the top of my head...no googling on that one lol

airpirate

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Re: W72 quadrajet cast number?
« Reply #4 on: April 26, 2017, 09:24:56 PM »
Impressive , I don't remember what I ate for breakfast:) ????



78 TA 6.6 W72 WS6
10 Land Rover
08 Dodge Ram
15 Ford Edge
03 Indian Motorcycle

Re: W72 quadrajet cast number?
« Reply #4 on: April 26, 2017, 09:24:56 PM »

TA78

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  • Agawam,Mass.
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Re: W72 quadrajet cast number?
« Reply #5 on: April 27, 2017, 06:54:14 AM »
17058263 W/4 SPD, 17058266 for auto

airpirate

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Re: W72 quadrajet cast number?
« Reply #6 on: April 27, 2017, 09:55:46 AM »
Cool.    Thanks guys



78 TA 6.6 W72 WS6
10 Land Rover
08 Dodge Ram
15 Ford Edge
03 Indian Motorcycle

airpirate

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Re: W72 quadrajet cast number?
« Reply #7 on: April 27, 2017, 07:00:29 PM »
Double checked mine it's
17058266.    Thanks again you guys



78 TA 6.6 W72 WS6
10 Land Rover
08 Dodge Ram
15 Ford Edge
03 Indian Motorcycle

Bandit818

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Re: W72 quadrajet cast number?
« Reply #8 on: February 04, 2019, 11:19:54 PM »
W72 carbs are 800CFM regular 400 carbs are 750CFM

oldskool

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Re: W72 quadrajet cast number?
« Reply #9 on: February 05, 2019, 12:34:02 AM »
W72 carbs are 800CFM regular 400 carbs are 750CFM

Sorry, but that is NOT correct !

All '76 & later Pontiac Q-jets are 800 cfm, including the 350 Q-jets, and even the 301 Q-jets. They are calibrated different. But, the throats are the same size & will flow the same amount of air. This also includes the 403 Olds Q-jets, and most of the Chevy Q-jets. The main difference in the 750 & 800 Q-jet is the primary venturi(throat) size. The larger venturis of the 800, will flow more air/fuel mixture.

Beginning back in the '60's, especially with Birds, Pontiac would limit the opening of the primary butterflies, in order to restrict flow & reduce power. That's why they rated the base '68 Bird 400 at 330hp, but basically the same base GTO 400 at 350hp. 

They probably did something similar on either the front or rear(or both) of the later Q-jets, especially on the smaller engines.

Of course, these restricted carbs can be modified for more flow & higher performance.
« Last Edit: February 15, 2019, 06:49:48 AM by oldskool »

Re: W72 quadrajet cast number?
« Reply #9 on: February 05, 2019, 12:34:02 AM »
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