Best intake manifold and carburetor for a 273

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Bossanova5

Bossanova5

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Hello All,

I bought a 66 273 that has a 2 barrel BBD carb on it.

I would like to upgrade to possibly a carter 4 barrel carb.

What's the best manifold and Carb to run on these engines?

Thanks in advance
 
Any factory iron 4bbl is a very good intake. You can save some weight with an Edelbrock Performer.

The small displacement engine can use a 500cfm Edelbrock. A 600 isn’t to large ether. I would use the AVS II style carb.
 
eddy performer with a 500~625 carter/eddy afb or AVS 2
(and that's performer, not RPM or air gap)

if you could find one and don't mind splashing the cash, eddy LD4-B would be awesome.

**double check that you have the later heads** early units had a different bolt angle and take a specific intake manifold that is unique.

are you going to do a cam as well?
 
Edelbrock SP2P
Edelbrock LD4B
or
Speedmaster Air Gap
 
Any 318 small port intake will work. Original 273 intake and Carter AFB works very good, I would think the AVS II would work well also, since you can adjust the secondary air valve. Same goes for a TQ or Quadrajet. Use a 68 up 340 throttle cable bracket. You can even use an original 340/360 intake both of which are very good for cheap. If you are running an automatic trans, make sure the kickdown linkage works and is adjusted correctly.
 
Super Victor and 1250 Dominator.


....and a .750 roller.
 
I'm going to try a Holley Street Dominator and an electric choke (800 ThermoQuad). I'm good as long as it works ok and makes a lot of noise. On my stock 273-2bbl Dart. Anytime I drive any of my cars that have a Thermoquad, I have to hear it just once!
 
If and if. If you have the money -and it will be alot- you could go with an Offenhauser dual quad and two 500cfm carburetors. If you're ok that this setup works great- but offers no improvement over a good single 4bbl carb it would sure sound wonderful when all the barrels are singing plus it's a looker when the hood is opened.

IMG_20230704_200935735.jpg
 
A nice cast iron 4 barrel do the job. I swapped my cast iron 4 barrel for a LD4B and I really didn’t notice much difference overall on my 273 hipo engine.
IMG_3914.jpeg
 
Last edited:
3forty said:
You need to put a red X on post #8
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:rofl: It's tough to figure who is looking for a laugh and who is serious. Sarcasm on a forum can be taken literally and misconstrued as the truth. :BangHead::BangHead:
 
Bossanova5 said:
Hello All,

I bought a 66 273 that has a 2 barrel BBD carb on it.

I would like to upgrade to possibly a carter 4 barrel carb.

What's the best manifold and Carb to run on these engines?

Thanks in advance
Click to expand...
CUDAVRT has a Edelbrock air-gap port matched intake and exhaust with a small Holley. It was pro built .030 over with Pertronic ignition. not dynoed, but we believe it makes about 275HP on regular gas. '66 block and 4-sp with an inland shifter. (started life as a slanty /auto) Note: the air-gap intake will require an aftermarket air cleaner to fit under the hood. I used the I6 radiator (re-cored) with a handmade shroud.

_7101033-Edit.jpg


_7101031.png
 
lemondana said:
I'm going to try a Holley Street Dominator and an electric choke (800 ThermoQuad). I'm good as long as it works ok and makes a lot of noise. On my stock 273-2bbl Dart. Anytime I drive any of my cars that have a Thermoquad, I have to hear it just once!
Click to expand...

I’ll be a bummer and tell you what you’ll experience.

Loss of low end torque
A gain in high rpm HP
Camshaft dependent, the two intakes will balance out around the same rpm area of approximately 4000/4500
You’ll pick up a usable 500 rpm up top and hang onto the power to 5500.

To make the most of this intake, a gear reduction and extra stall in the converter (and matching the camshaft of replaced) will help abate low end torque loss, get you into the camshaft power band quicker.
 
rumblefish360 said:
I’ll be a bummer and tell you what you’ll experience.

Loss of low end torque
A gain in high rpm HP
Camshaft dependent, the two intakes will balance out around the same rpm area of approximately 4000/4500
You’ll pick up a usable 500 rpm up top and hang onto the power to 5500.

To make the most of this intake, a gear reduction and extra stall in the converter (and matching the camshaft of replaced) will help abate low end torque loss, get you into the camshaft power band quicker.
Click to expand...
I have no low end torque and I have no high rpm horsepower with 2.71 gears, 225-70/15 rear tires and the factory single exhaust. I drive this car on the Interstate quite frequently.
 
lemondana said:
I have no low end torque and I have no high rpm horsepower with 2.71 gears, 225-70/15 rear tires and the factory single exhaust. I drive this car on the Interstate quite frequently.
Click to expand...
Then don’t swap the Holley intake.
Use a dual plane. Factory iron or a Performer.
 
I believe anybody can figure out I'm sarcastic talkin about a Super Victor and .750 roller for a 273. That said, my serious recommendation would be a stock Commando 4 barrel intake and a nice modern Edelbrock 500 AVS. That's be hard to beat, IMO.

....and @3forty, I'm glad to see I am still living in your mind. That makes me feel so special, you'll just never know. lol
 
RustyRatRod said:
I believe anybody can figure out I'm sarcastic talkin about a Super Victor and .750 roller for a 273. That said, my serious recommendation would be a stock Commando 4 barrel intake and a nice modern Edelbrock 500 AVS. That's be hard to beat, IMO.
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my only gripe on the commando intake is that those seem to be entering "LD territory" price wise and for that money i think there's much better pieces out there. it also limits you to a square bore (without an adaptor, but then hood clearance could be an issue) if that's an important factor.

i think it'd be fine for the application, but there's better options imo
 
junkyardhero said:
my only gripe on the commando intake is that those seem to be entering "LD territory" price wise and for that money i think there's much better pieces out there. it also limits you to a square bore (without an adaptor, but then hood clearance could be an issue) if that's an important factor.

i think it'd be fine for the application, but there's better options imo
Click to expand...
That's a very valid point and one that I'd say maybe find a decent deal on a regular Edelbrock performer. I just gave one to a friend's father in law, although it was for a small block Chevy, so deals are out there, I'm sure.
 
RustyRatRod said:
That's a very valid point and one that I'd say maybe find a decent deal on a regular Edelbrock performer. I just gave one to a friend's father in law, although it was for a small block Chevy, so deals are out there, I'm sure.
Click to expand...
I just got this for $136(cash I had in my pocket) for my commando.

image.jpg
 
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