Author Topic: More carb info help needed.  (Read 1958 times)

Offline 4SPEED76

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More carb info help needed.
« on: July 27, 2017, 11:00:16 AM »
I have a few different Q-Jets laying around and I am trying to decide what one to build.  One is for sure an 800CFM and the part number is 17086249 non electric carb, and the others are 750CFM carbs.  I would like to know if the 800 would be a bit too large for my engine.  Here is the engine specs.

350 4 bolt bored .030 over
Hyper flat top pistons with 2 valve reliefs
9.87:1 compression
Edelbrock easy street 64cc chambers, 2.02/1.60 valves
Edelbrock 2601 intake manifold
Comp Cams ultra pro magnum rockers
Comp cams 280H cam
Hooker competition full length headers.

Offline 4SPEED76

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Re: More carb info help needed.
« Reply #1 on: July 27, 2017, 11:02:21 AM »
I have cliffs bible on Q-Jets, and would like to know what rebuild kit I should buy and what recipe would work best with my combo.  Thanks for any input

Offline Ethan1

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Re: More carb info help needed.
« Reply #2 on: July 28, 2017, 02:31:21 PM »
 Is that a performance cam? Or mild cam? I think recipe #2 would be a good starting point. I would also go with Cliff's HP kit. Comes with everything except for choke pull-off and metering rods/jets.
Ethan

1972 Chevelle

(oo______oo)

Offline unruhjonny

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Re: More carb info help needed.
« Reply #3 on: July 28, 2017, 09:46:35 PM »
As I have come to understand it, one of the great things about the Quadrajet design, is that there's no such thing as too much carb;
the "800cfm" castings were used on a variety of engine combinations - many of which, when conventional logic is used, would indicat that 800cfm is too much.
IIRC the spread bore design essentially feeds as much as you need.

I would use the best core carb you have as the basis of your carb.

But that's as far as my opinion goes... :)

Offline Cliff Ruggles

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Re: More carb info help needed.
« Reply #4 on: July 29, 2017, 03:37:10 AM »
Pretty "hefty" cam for the little 350 engine.  Expect low vacuum at idle, stinky exhaust and lacking power below about 3000rpms.

You will need a LOT of idle fuel and bypass air for that combination.  Hopefully it's for a street/strip car with a lot of gear and converter......Cliff