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Old Feb 20, 2026 | 09:53 PM
  #856  
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The Holley Truck Avengers look nice but I think a regular old Quadrajet is what I’ll be using. I have maybe half a dozen on the shelf and they’re supposed to be great off road carbs. Just need to use an adapter or an Offy intake for a spreadbore.
 
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Old Feb 20, 2026 | 10:56 PM
  #857  
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The ol 71 came with a very old, very very leaky 4bbl Quadrajet on it. It probably had not ran in many months or even longer...like a year or more. The owner drove (in a big open field), so I could make sure the trans shifted and the xfer case worked. I had to constantly dump gas in the carb during the test drive.

With no windshield and once un pinned the fiber glass hood and took it off, I poked a small hole in a water bottle cap, so I could drip fuel in it, while leaning thru the WS frame. We made it a small lap and then 1/2 way back to the house it finially gave up running all together. A backhoe pushed it on the trailer.

They say you can even run the Quadrajet mounted backwards. Too run the 2 big barrels all the time and the 2 smaller ones when needed, in stead of the other way around. Or some suck talk like that, at least that is urban legend.

AI can I run a Quadrajet carb backwards? "Yes, you can run a Rochester Quadrajet carburetor backwards (rotated 180*) on an engine, a trick sometimes used in off-road applications to prevent fuel slosh/stumbling due to its center-mounted fuel bowl. This setup requires a special adapter to match the bolt pattern and a modified throttle cable, but it functions well. "

While common in specialized off-road vehicles (e.g., old Broncos), this is not a typical street application setup.
Key considerations for running a Quadrajet backward include:
  • Off-Road Benefits: The center-mounted float bowl prevents stalling at steep, extreme angles.
  • Adapter Required: A specific adapter is needed to mount the spread-bore carburetor backward on a standard intake manifold.
  • Throttle Cable Issues: The throttle linkage moves to the front, necessitating a longer, custom-routed throttle cable to reach it.
  • Fuel Inlet Access: The fuel inlet will move to the rear of the engine, requiring new fuel line routing.
https://ck5.com/forums/threads/rebui...ffroad.126563/

https://classicbroncos.com/forums/th...uestion.47864/

I slapped on a 4 bbl Edelbrock on, since I had one on the shelf and got to working on all the rest. When that carb almost killed me, cause the Bronco died on a VERY steep long down hill. No running Bronco='s NO PS, NO power brakes ='s almost dieing. I went to a MC 2bbl for a while, yes it ran great, but just not enough power.

So after some off road tricks to the Edelbrock, that made it better but still not all that. I ran across a smoking deal on the Holley Off Road carb. It is great for of roading, but crappy IMO on flat terrain.



 
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Old Feb 21, 2026 | 08:59 AM
  #858  
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Originally Posted by 77&79F250
The ol 71 came with a very old, very very leaky 4bbl Quadrajet on it. It probably had not ran in many months or even longer...like a year or more. The owner drove (in a big open field), so I could make sure the trans shifted and the xfer case worked. I had to constantly dump gas in the carb during the test drive.

With no windshield and once un pinned the fiber glass hood and took it off, I poked a small hole in a water bottle cap, so I could drip fuel in it, while leaning thru the WS frame. We made it a small lap and then 1/2 way back to the house it finially gave up running all together. A backhoe pushed it on the trailer.

They say you can even run the Quadrajet mounted backwards. Too run the 2 big barrels all the time and the 2 smaller ones when needed, in stead of the other way around. Or some suck talk like that, at least that is urban legend.

AI can I run a Quadrajet carb backwards? "Yes, you can run a Rochester Quadrajet carburetor backwards (rotated 180*) on an engine, a trick sometimes used in off-road applications to prevent fuel slosh/stumbling due to its center-mounted fuel bowl. This setup requires a special adapter to match the bolt pattern and a modified throttle cable, but it functions well. "

While common in specialized off-road vehicles (e.g., old Broncos), this is not a typical street application setup.
Key considerations for running a Quadrajet backward include:
  • Off-Road Benefits: The center-mounted float bowl prevents stalling at steep, extreme angles.
  • Adapter Required: A specific adapter is needed to mount the spread-bore carburetor backward on a standard intake manifold.
  • Throttle Cable Issues: The throttle linkage moves to the front, necessitating a longer, custom-routed throttle cable to reach it.
  • Fuel Inlet Access: The fuel inlet will move to the rear of the engine, requiring new fuel line routing.
https://ck5.com/forums/threads/rebui...ffroad.126563/

https://classicbroncos.com/forums/th...uestion.47864/

I slapped on a 4 bbl Edelbrock on, since I had one on the shelf and got to working on all the rest. When that carb almost killed me, cause the Bronco died on a VERY steep long down hill. No running Bronco='s NO PS, NO power brakes ='s almost dieing. I went to a MC 2bbl for a while, yes it ran great, but just not enough power.

So after some off road tricks to the Edelbrock, that made it better but still not all that. I ran across a smoking deal on the Holley Off Road carb. It is great for of roading, but crappy IMO on flat terrain.
Sounds like a fun test drive!

I recently bought 60 or so vintage carburetors for $500. It was from a shop that closed down and they never threw away carburetors they removed. Ended up with a bunch of Q-jets and Carters, including a Q-jet that I sold for $500 (390 hp Corvette carb), Motorcraft 2bbl and 4bbl, several Autolite 4100's, a few Holleys, and about 10 Edelbrocks. Sold everything except for most of the Q-jets, and a few look like they've been rebuilt and never installed. Figure I might as well give 'em a shot since I have a bunch and they're supposed to work well.






 
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Old Feb 22, 2026 | 10:04 PM
  #859  
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Yes it looks like you are busting at the seams with carburetors. I guess I need to do the research and rebuild that Quadrajet and see how well it works backwards.
 
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Old Mar 9, 2026 | 12:13 AM
  #860  
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Well I got a little side tracked other than pulling the Bronco out of the garage for the last few weeks. So now have a 3 ton mini split installed in the garage and have been cleaning like a mad man in there to get my garage back. I had turned a 30' work bench into a 30' storage shelf. Of course now that I cleaned, I can not find anything.

 
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Old Mar 27, 2026 | 06:05 PM
  #861  
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Got a smoking FB MP deal on a Holly Sniper kit the other day. So changes are a coming.....
 
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