Hey, question about carb swaps

[thirteenwithinfinity]

I recently moved to a new place that doesn't require emissions anymore. So out came all of that from my Malibu, haha.

Reguardless, I came across a Holly 390CFM carb. Will this fit onto the 267 and will it work properly without much issue?

 

[pontiacman469]

dont like the quadbog?tuned right they can be the best carb,beats a holley 😀

 

[85 Cutlass Brougham]

dont like the quadbog?tuned right they can be the best carb,beats a holley 😀

It's probably a 2 barrel car since it has a 267, so it would be a Dualjet, not a Quadrajet.

As for the question, I first off would keep all that smog crap safe and sound somewhere since the possibility of signing the Kyoto Protocol in the future may dictate emissions testing in your area.

As for the Holley 390, you have to remember that this carb is designed and tuned from the factory to work on a tunnel ram, so it may need to be modified to work well on your 267. It will also require a new intake if you have a 2 barrel, or a ghetto type adapter if it is a 4bbl. For that, I would run something like an Edelbrock Performer as it has a dual bolt pattern. Now if you already have a Quadrajet, there is no real reason to change it provided it is from a small displacement engine (for the idle feed restrictions.). Just get it gone through professionally and be sure the throttle shafts are tight. I would also keep the stock air filter base for a 4 barrel and add a secondary snorkel with ducting to bring in colder outside air. This will flow more than enough air to feed your baby V8, and the filters will last longer than an open element. Plus, SBC's need a quirky offset base for an open element when using a standard 14 in element, so stock here saves you money. I would also go through the HEI and be sure that the advance bushings still exist. It's almost 30 years old, and many of them are very neglected by now.

I run a Quadrajet and a rare dual snorkel 3rd gen Camaro air filter base on my car and like it better than the aftermarket carbs I had in the past. It fits and works better than the Edelbrock, and it requires no funky little adapter parts to make everything work together right. Remember that it is not just the carb and intake you need, you also need brackets for the throttle cable, a TV cable bracket to maintain the right geometry, fuel line and filter, and an air filter spacer if you run the Holley or Edelbrock carbs. All this adds cost to the conversion. It will not make the car run any better than a good, cheap Quadrajet.

 

[thirteenwithinfinity]

dont like the quadbog?tuned right they can be the best carb,beats a holley 😀

It's probably a 2 barrel car since it has a 267, so it would be a Dualjet, not a Quadrajet.

As for the question, I first off would keep all that smog crap safe and sound somewhere since the possibility of signing the Kyoto Protocol in the future may dictate emissions testing in your area.

As for the Holley 390, you have to remember that this carb is designed and tuned from the factory to work on a tunnel ram, so it may need to be modified to work well on your 267. It will also require a new intake if you have a 2 barrel, or a ghetto type adapter if it is a 4bbl. For that, I would run something like an Edelbrock Performer as it has a dual bolt pattern. Now if you already have a Quadrajet, there is no real reason to change it provided it is from a small displacement engine (for the idle feed restrictions.). Just get it gone through professionally and be sure the throttle shafts are tight. I would also keep the stock air filter base for a 4 barrel and add a secondary snorkel with ducting to bring in colder outside air. This will flow more than enough air to feed your baby V8, and the filters will last longer than an open element. Plus, SBC's need a quirky offset base for an open element when using a standard 14 in element, so stock here saves you money. I would also go through the HEI and be sure that the advance bushings still exist. It's almost 30 years old, and many of them are very neglected by now.

I run a Quadrajet and a rare dual snorkel 3rd gen Camaro air filter base on my car and like it better than the aftermarket carbs I had in the past. It fits and works better than the Edelbrock, and it requires no funky little adapter parts to make everything work together right. Remember that it is not just the carb and intake you need, you also need brackets for the throttle cable, a TV cable bracket to maintain the right geometry, fuel line and filter, and an air filter spacer if you run the Holley or Edelbrock carbs. All this adds cost to the conversion. It will not make the car run any better than a good, cheap Quadrajet.

Hmm, okay. Thanks D: That's alot of stuff to look through, haha.

I've got a 2bbl on the engine now and kinda wanna get rid of it. I can trade my 390 away for a quadrajet.. Would that be the better thing to do? And maybe the easier conversion?

 

[85 Cutlass Brougham]

It is definitely easier, but it's only a good idea if the engine the car was originally from is similar in displacement to yours. Otherwise, it will be rich at idle and part throttle no matter what you do because the idle feed circuit will be too big. The application to pull one from that comes to mind is maybe the Buick 4.1 V6 with a 4 bbl. You really want a carb made after around 1977 or so and not an earlier one, or else I would say to go for the one off a 1967-1969 Pontiac OHC L6 with the 4bbl HO option.