RE: [Cadillac_Performance_Association] Carb for 73 472
- Sounds like your choke is not closing when cold.
Is the carb clean? Start by a good cleaning with carb cleaner and then some
WD40 around the choke plate and secondaries. Make sure the small links on
the passenger side are clean and free to move. With the car cold both the
secondaries and the primaries should be closed from view...completely
From: Jeremy Stevens [mailto:jcopp24@...]
Sent: Tuesday, March 08, 2005 8:27 AM
Subject: Re: [Cadillac_Performance_Association] Carb for 73 472
Thanks for the awesome info on the carbs. My question is on the stock
Quadrajet 400 that is on my 1968 Sedan De Ville. I think that my carburetor
is fouled but not being a mechanic I would like a second opinion. My engine
has about 38250 miles and it is original miles ( single owner before me )
driving home last summer I went to accelerate and felt the engine choke up.
The car obviously did not accelerate so I backed off the peddle and stayed
at the speed the engine seemed to like for the rest of the ride.
When I returned home I shut down the car and thought that maybe I had
bought some bad gas because I had bought it in a small town. So I went and
bought some drygas and filled the engine back up with regular unleaded. I
have never used lead additive nor did the owner before... you might tell me
that is my problem too... I have been advised either way on that question I
just did what the previous owner had done.
Either way now when I go outside to start the car I have to use a
starter fluid/spray ( I think because it is cold ) But I have to give the
car gas other wise it will stall out imediatly. Even after I let the car run
for a half and hour by holding the gas down a little the car still can not
There is my problem... I have been told my carb is probably clogged
up??? That my timing belt has been advanced or retarded just enough so that
this is happening??? Or that I have a clogged fuel pump even... I know you
cant see the car but any advice on where to start would be great.
>From: Preston III <prestoniii2002@...>Yahoo! Groups Links
>Subject: Re: [Cadillac_Performance_Association] Carb for 73 472
>Date: Mon, 7 Mar 2005 12:24:26 -0800 (PST)
>Then grab a used original from the wrecking yard, and pay
>a reputable mechanic to rebuild it.
>There's a place in California called "The Carburetor Shop"
>that specializes in Quadrajets. Let them do a performance
>rebuild. It'll cost you about $200-$250 for the rebuild.
>They do fantastic work. PLUS, I think Edelbrock sells NEW
>Quadrajets for around $350-$450.
>The small front venturi of the Quadrajet is where these
>carbs get the fuel economy that they provide, and no
>other aftermarket carburetor has the small primary
>venturi. And the ultra LARGE secondaries make up for
>the small primaries when you step on the "GO" pedal.
>Your factory Quadrajet probably measures something close to
>900 CFM with all 4 venturi full open, but the Quadrajet
>is a variable CFM carburetor, and calibrates itself
>according to the air that's needed, and NOT what it's
>capable of. Realistic calculations indicate that your
>engine could live with a 650 CFM fixed flow. On a low
>performance luxo-barge, 600 would probably be even better
>for quicker throttle responce and better economy.
>A replacement carb like a holley, or carter just can't match
>the fuel economy of your original, and the performance gain
>will not be enough to offset the extreme loss in gas mileage.
>These carb's are fixed CFM, and are jetted to provide the
>appropriate amount of fuel at full flow, once you're into
>the secondary circuit.
>If you put a holley on that engine, you wont be able to
>pass a filling station. They're good carb's, but their
>purpose is not for a daily driven boat. If you're building
>a high performance car, there are other things that you need
>to look into before you get to the carb; things like exhaust,
>intake manifold, ignition systems, etc.
>--- "Tony D. Cato" <deacon_cato@...> wrote:
> > I need a new carb and rebuilding the original is not an option. What
> > size carb and by who? THANKS!
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