Author Topic: Which carb for the application  (Read 4706 times)

Offline Hotrodrobert

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Which carb for the application
« on: December 08, 2008, 10:05:08 AM »
Carbs I have on hand are:
7058213
17057512
7045512
17080512
7040511
7043202
7042240
17085226
I need one for a near stock 390 Galaxie with auto, 383 SBC with 234*@.050" lift intake, EQ 220cc intake runnners, Air Gap intake, '70 Camaro 700R, 3.73 gears, street car, and 402BBC 8.7:1, 214/224 @.050, 112 lobe spread in a Chevy pickup for heavy towing and hauling.
Which one for which app????
Thanks in advance!!!! ;D

Offline Cliff Ruggles

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Re: Which carb for the application
« Reply #1 on: December 09, 2008, 04:57:15 AM »
Robert, let the carburetors features be the guide to selecting it for the application.  In other words look at the fuel inlet location, throttle linkage, type of choke, vacuum fittings, etc.

For example, the Camaro with the 700-R4 will require a hook up point for the TV cable.  Most Chevy carburetors set up originally for the TH350 will have the correct hook up point, some of the later carburetor numbers on your list may already have a TV cable hook up point for the 700-R4?

Side fuel inlet carburetors are prefered in most applications since the fuel filter housing will not be too close to the thermostat housing on short intake manifolds.

If the carb has a choke on the carb, it is easily converted to electric.

Quite a few of the carburetor numbers that you listed are divorced choke models.  These are difficult to convert to electric choke, and work best with the factory intake manifolds and factory choke coils/linkage.  This assumes that you plan on using a choke in the first place, we do NOT consider on necessary for street/strip cars or cars that are only operated in warmer weather.

My first choice is ALWAYS a later carburetor with the latest APT system and hot air choke.  This way we get the best features of the q-jet, and we can add an electric choke if a choke is required for the application.  Hope this helps some?......Cliff
« Last Edit: December 09, 2008, 01:17:37 PM by cliffq »

Offline Hotrodrobert

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Re: Which carb for the application
« Reply #2 on: December 09, 2008, 07:09:19 AM »
Thanks, Cliff.  What I really need to know is which are the closest to the needed calibration so I don't have as much tuning work to do.  If you don't have the specific info or don't have time, I will contact you with the specifics for the calibration kits.

Offline Cliff Ruggles

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Re: Which carb for the application
« Reply #3 on: December 12, 2008, 06:06:11 PM »
Robert, I wished it were that simple.  Like anything else with this hobby, the best results are obtained by tuning the fuel and spark curves EXACTLY for the application.   The vast majority of the q-jets produced were subject to tight emission standards and delivered on "low" performance engines.  Expect to have to tune any of the part numbers you listed in just about every area for the application it will end up on.....Cliff