Put a 4bbl. carb on an original 2 bbl. 283?

[Rickchevy56]

Hello All (and thanks to Bow tie)
This is regarding a Chevy 283 I would like to put in my '64 Impala. The buyer mentioned in my previus post has a rebuilt long block with a 2 bbl carb intake manifold. The block # 3789935 (the 3 was blurry) mortec.com i.d."s as '61-64 2 bolt main which my book says has from 170-195 HP. I just paid last year $265 to rebuild my 4 bbl.stock carb which is on the tired 350 in the car.
The guy may have a 2bbl. carb of unknown quality he could give me free or he could sell my an aluminum Edelbrock performer intake for $50. Would that work out ok? I'm not interested in racing.
By the way my brother seems to think that 2bbl. carbs don't choke as much as 4 bbl. when cold. What you say?
Thanks , Rick

[maxwedge]

What engine did the 4bbl come off and what is it exactly?

[Blue Bowtie]

Is the 4BBL an original 4Gc or the later M4MV?

4GC: http://www.carburetorfactory.com/expvw26.html

4MV: http://www.carburetorfactory.com/expvw27.html

The 4G/4C is a mechanical secondary, and even though it's smaller, may not be suitable for a smaller displacement engine like the 283. The 4MV (QuadraJet) is a vacuum secondary, and can be tuned/set up for proper operation on even a 265.

[Rickchevy56]

Hi Guys
The 4bbl. carb is from a '76 Caprice with a 350. The markings say Rochester, Quadra Jet on the driver side of the carb are 17057504 1747 AYO
2. What do you think of my brother's viewpoint that 4bbl. carbs use more gas and choke/sputter more than 2 bbl.s when cold?
Thanks much, Rick the

Originally Posted by Blue Bowtie

Is the 4BBL an original 4Gc or the later M4MV?

4GC: http://www.carburetorfactory.com/expvw26.html

4MV: http://www.carburetorfactory.com/expvw27.html

The 4G/4C is a mechanical secondary, and even though it's smaller, may not be suitable for a smaller displacement engine like the 283. The 4MV (QuadraJet) is a vacuum secondary, and can be tuned/set up for proper operation on even a 265.

[silicon212]

Originally Posted by Rickchevy56

Hi Guys
The 4bbl. carb is from a '76 Caprice with a 350. The markings say Rochester, Quadra Jet on the driver side of the carb are 17057504 1747 AYO
2. What do you think of my brother's viewpoint that 4bbl. carbs use more gas and choke/sputter more than 2 bbl.s when cold?
Thanks much, Rick the

I think your brother's high on drugs and he needs to share.

The Quadrajet will make your engine more efficient than a 2GC any day - as long as you don't go leadfooting everywhere you go. I've also had less 'sputtering' with a Qjet than with any 2GV/2GC I've ever owned (and I've owned several through the years).

[bobss396]

I'm partial to the good old 2GC carbs. They always ran smoothly and were a snap to rebuild. I always ran an aftermarket Holley gas filter on mine and never had a problem with them. They are even cheap enough to buy brand new, some big carb makers like Carter make great knockoffs of them.

Bob

[777stickman]

If you do put that Q-Jet on then the performer manifold would be a great choice as it matches up to the Q-Jet "spread bore" pattern (no adapters needed). 2 problems with the Q-Jets.

1. Fuel bowl leakdown from the bottom plugs (epoxy fixes this).
2. Primary throttle shaft bore wear causing vacuum leak (not an easy fix).

[comp]

Originally Posted by silicon212

I think your brother's high on drugs and he needs to share.

The Quadrajet will make your engine more efficient than a 2GC any day - as long as you don't go leadfooting everywhere you go. I've also had less 'sputtering' with a Qjet than with any 2GV/2GC I've ever owned (and I've owned several through the years).

i agree

[Rickchevy56]

Hi Guys,
thanks for the advice. I also talked to 2 carb shops about the QuadraJet 4bbl. going on the 283; one said it would be ok, the other said it would be too much carburation (CFM) and the smaller Eldelbrock 500 4bbl would be better what ya think?
also both said that a 4 bbl should get better gas mileage than a 2bbl.
Thanks
Rick chevy56.

Originally Posted by Rickchevy56

Hello All (and thanks to Bow tie)
This is regarding a Chevy 283 I would like to put in my '64 Impala. The buyer mentioned in my previus post has a rebuilt long block with a 2 bbl carb intake manifold. The block # 3789935 (the 3 was blurry) mortec.com i.d."s as '61-64 2 bolt main which my book says has from 170-195 HP. I just paid last year $265 to rebuild my 4 bbl.stock carb which is on the tired 350 in the car.
The guy may have a 2bbl. carb of unknown quality he could give me free or he could sell my an aluminum Edelbrock performer intake for $50. Would that work out ok? I'm not interested in racing.
By the way my brother seems to think that 2bbl. carbs don't choke as much as 4 bbl. when cold. What you say?
Thanks , Rick

[silicon212]

Originally Posted by Rickchevy56

Hi Guys,
thanks for the advice. I also talked to 2 carb shops about the QuadraJet 4bbl. going on the 283; one said it would be ok, the other said it would be too much carburation (CFM) and the smaller Eldelbrock 500 4bbl would be better what ya think?
also both said that a 4 bbl should get better gas mileage than a 2bbl.
Thanks
Rick chevy56.

The beauty of the Quadrajet design is that the engine takes only what it needs. Although the Q-jet is capable of 780 SCFM, it will only deliver what the engine can take, which makes it friendly to the 283.

[Blue Bowtie]

A Holley 500 (even a vacuum secondary) may be too much carb for a street-driven engine. Most of them come out of the box roughly calibrated for a 350, not a 283.

With a Holley, you're looking at changing all four main jets, and to do it properly, drill out and press in idle air bleeds (it's likely that they are too big for a 283), change the secondary vacuum diaphragm spring (likely several times), possibly change the secondary (inner) venturis at least on the primary bores for best vacuum signal, and if it's a mechanical secondary, live with a permanent bog or needlessly rich secondary mixture.

Even after you re-jet, adjust, and tweak the Holey, its primaries are larger than the Rochester, and will not meter fuel as efficiently.

With the Q-Jet, you'll have to change two main jets, probably change the secondary metering rods (maybe not), MAYBE change the power valve if you have a more aggressive cam (you would have to do the same for BOTH sides of the Holley), and adjust the secondary AV spring windup.

The QuadraJet was used successfully on engines as small as the Pontiac 240 CID inline six.

[Blue Bowtie]

I guess I was mistaken - That OHC Pontiac six with the QuadraJet was only 230 inches. 40-some year old memories are a dangerous thing...

It still made 215 HP.

[comp]

i vote Q-Jet

[maxwedge]

I vote original design 4gc carb.