QUADRA JUNK... what to replace with

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krisnowicki

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I have a q jet that the diaphram is cracked on... and it is just spitting up fuel every where. Any good spread bores out there? Do thos spread bore to straight bore adapters work? should I just change the intake?
 
Fishermark

Fishermark

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Re: QUADRA JUNK... what to replace with

I realize it is not a spread bore, but I really like the Edlebrock Performer - Marine version. Yes, it is a square bore, but you might find you have enough "meat" around the intake to bolt it up without an adapter. The car in my avatar is mine, and I have the Edlebrock Performer intake - which is a spreadbore intake - and I am running Edlebrock's thunder series carb, (essentially the Performer carb) which is a square bore. It bolted up with no vacuum leak issues without an adapter.
 
Bifflefan

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Re: QUADRA JUNK... what to replace with

The adapters work well, and they give you a bit more torque in the bottom end. Probably not so much as you would notice with out a dyno tho.

As for the carbs, Holly also makes or made a spread bore that is a direct replacement, but they dont make a marine one in a spread bore.
I go with a Holly marine,, but im a big Holly fan.
 
Apollo75

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Re: QUADRA JUNK... what to replace with

You fellas keep bad mouth-in Q-jets your gonna get me all riled up :eek:

All you need is a couple screw drivers, needle nosed pliers and some wire drill bits. That boat will be singing across the water. Nothing like the sound of those big secondarys opening :D


What diaphragm is cracked ?

OFM

-----------------------------------------------------------
If the boat is not sinking or on fire, Relax :D
 
J

John_S

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Re: QUADRA JUNK... what to replace with

Fishermark said:
I realize it is not a spread bore, but I really like the Edlebrock Performer - Marine version. Yes, it is a square bore, but you might find you have enough "meat" around the intake to bolt it up without an adapter. The car in my avatar is mine, and I have the Edlebrock Performer intake - which is a spreadbore intake - and I am running Edlebrock's thunder series carb, (essentially the Performer carb) which is a square bore. It bolted up with no vacuum leak issues without an adapter.
Click to expand...

Certain (most?) Edelbrock Performer intakes will handle a spread or square bore, which they are designed to do. If krisnowicki has the stock cast-iron hi-rise intake, it will handle either, as well. If he has the low-profile cast-iron it will not bolt up without an adapter. I think I remember him asking about the hi-rise, but not sure.
 
Don S

Don S

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Re: QUADRA JUNK... what to replace with

I have a q jet that the diaphram is cracked on...
Click to expand...

:confused: :confused: Q Jets, don't have diaphrams :confused:

What do you have going on, really. Pictures would help.
 
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krisnowicki

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Re: QUADRA JUNK... what to replace with

Brass piece on top where gas spits out of on the small side is cracked and pouring gas out.new carb a must sorry fo the wrong term.
 
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windsors03cobra

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Re: QUADRA JUNK... what to replace with

Apollo75 said:
You fellas keep bad mouth-in Q-jets your gonna get me all riled up :eek:

All you need is a couple screw drivers, needle nosed pliers and some wire drill bits. That boat will be singing across the water. Nothing like the sound of those big secondarys opening :D


What diaphragm is cracked ?

OFM

-----------------------------------------------------------
If the boat is not sinking or on fire, Relax :D
Click to expand...

LoL I will agree they do sound pretty mean opening up with the air cleaner lid flipped over :D
I also call em Quadra Bogs and Quadra Sewers.
Remember Thermo Quads ? Thermo Bogs, Thermo Junk, Meltdown Carbs, fans of those out there too. All good carburetors.
 
justchange

justchange

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Re: QUADRA JUNK... what to replace with

Edelbrock makes a Q-jet replacement. They are about $500 new and $300 reman.


Another option is to check local salvage [recycling] yards. If they don't have what you're looking for, have them look for it.

From what I remember, most auto salvage yards have some carb parts for most every carb made.
 
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sagrzmnky

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Re: QUADRA JUNK... what to replace with

Q-jets are easy to rebuild. I have been turning wrenches professionally for 20 yrs and the one thing I always liked about the Q-jet is once you get the idle/air set right, you hardly ever have to mess with it again. I have had hollys and you are constantly doing tweeks here and adjustments there. For a guy that works on cars all day long, I don't want to have to come home and do the same to my own truck or boat. Racers love hollys because they love constantly tweeking, but not me. Nothing sweeter than when those secondarys open. If I were going to replace it though, I would find an edelbrock or carter (same thing). I think you can buy an adapter at any auto parts store.
 
Apollo75

Apollo75

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Re: QUADRA JUNK... what to replace with

Show a little respect --- that is 850-cfm of Thermo-Quad on a 12.5 to 1 compression ratio 389 running a custom built Crower cam in a 1964 GTO --- Run well when you know what you are doing.

The Q-jet will adapt from a small 6-cylinder to a 502 cu inch --- it will adjust to changing loads with the secondary air valve and provide 650 to 800-cfm depending on selection. It has great throttle response by design of the small primarys and fine atomization provided by the multiple main metering cluster.

A standard mechanical secondary Holly just by the design can not adapt to changing load and will bog much more than a Q-jet. A vacuum secondary Holly is needed for good response with no bog and the carb selection needs to be based on the primary bore diameter for good throttle response at low rpm.

A mild 350 cubic inch in a boat can barely use 600-cfm with the best heads turning 4500-rpm. A Q-jet will adapt to this lower cfm and run fine.


OFM
 
skargo

skargo

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Re: QUADRA JUNK... what to replace with

Wow, haven't heard the unearned nickname quadrajunk used in many years. Obviously you are not a muscle car guy. Q's are GREAT carbs when built and tuned right, and more efficient than any Holley or E carb can be.

Funny, years ago people pulled them off and trashed them for aftermarket carbs, now all the GM musclecar guys use good q-jets on their built engines.
 
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fishseeker

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Re: QUADRA JUNK... what to replace with

Gota love a good tuned quadrapuk! Just SET IT AND FORGET IT:D Or put on a Holley and chase leaks!!!!!!
 
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