3X2 Carbs for a 70 BB
Thread Starter
Team Owner
Joined: Jul 2004
Posts: 40,412
Likes: 792
From: Redondo Beach, California
3X2 Carbs for a 70 BB
I have the original 3X2 carbs from my 69. I'm thinking about having them rebuilt to install on the 70 BB. The carbs were working fine when I removed them in the early 1980's. I'm thinking about a rebuild from either Holley or All American Carbs (Florida). I'd like to buy all new if possible. Holley sells new repro 3X2 carbs set up for the Chrysler/Dodge 440 cubic inch cars of the 70's (?) Anyone used these carbs on a Corvette?
I think the stock 3X2 69 carbs would flow 350 cubic inches in the outboards and 250 cfm in the center carb. Does anyone know if this is true? I think the Chrysler/Dodge 3X2 carbs were 500 cfm for the outboards and 350 cfm for the center.
If I use the 3X2's on my 70, I do have a 68/69 rectangular port manifold. I also have a 67 rectangular port manifold which I could also use, but I'd have to go to a L88 hood since the 67 manifold has a higher rise.
BTW...the 3X2 carb configuration was never available for the 70 BB's, but the 70 AIM does show a 3X2 carb option for the 70 and has assembly line instructions! Obviously the 3X2 was never a 70 option but since their installation is in the AIM, GM came close to offering them as an option.
Thanks
I think the stock 3X2 69 carbs would flow 350 cubic inches in the outboards and 250 cfm in the center carb. Does anyone know if this is true? I think the Chrysler/Dodge 3X2 carbs were 500 cfm for the outboards and 350 cfm for the center.
If I use the 3X2's on my 70, I do have a 68/69 rectangular port manifold. I also have a 67 rectangular port manifold which I could also use, but I'd have to go to a L88 hood since the 67 manifold has a higher rise.
BTW...the 3X2 carb configuration was never available for the 70 BB's, but the 70 AIM does show a 3X2 carb option for the 70 and has assembly line instructions! Obviously the 3X2 was never a 70 option but since their installation is in the AIM, GM came close to offering them as an option.
Thanks
Drifting
Joined: Jan 2014
Posts: 1,866
Likes: 140
From: Sadieville Kentucky
I have the original 3X2 carbs from my 69. I'm thinking about having them rebuilt to install on the 70 BB. The carbs were working fine when I removed them in the early 1980's. I'm thinking about a rebuild from either Holley or All American Carbs (Florida). I'd like to buy all new if possible. Holley sells new repro 3X2 carbs set up for the Chrysler/Dodge 440 cubic inch cars of the 70's (?) Anyone used these carbs on a Corvette?
I think the stock 3X2 69 carbs would flow 350 cubic inches in the outboards and 250 cfm in the center carb. Does anyone know if this is true? I think the Chrysler/Dodge 3X2 carbs were 500 cfm for the outboards and 350 cfm for the center.
If I use the 3X2's on my 70, I do have a 68/69 rectangular port manifold. I also have a 67 rectangular port manifold which I could also use, but I'd have to go to a L88 hood since the 67 manifold has a higher rise.
BTW...the 3X2 carb configuration was never available for the 70 BB's, but the 70 AIM does show a 3X2 carb option for the 70 and has assembly line instructions! Obviously the 3X2 was never a 70 option but since their installation is in the AIM, GM came close to offering them as an option.
Thanks
I think the stock 3X2 69 carbs would flow 350 cubic inches in the outboards and 250 cfm in the center carb. Does anyone know if this is true? I think the Chrysler/Dodge 3X2 carbs were 500 cfm for the outboards and 350 cfm for the center.
If I use the 3X2's on my 70, I do have a 68/69 rectangular port manifold. I also have a 67 rectangular port manifold which I could also use, but I'd have to go to a L88 hood since the 67 manifold has a higher rise.
BTW...the 3X2 carb configuration was never available for the 70 BB's, but the 70 AIM does show a 3X2 carb option for the 70 and has assembly line instructions! Obviously the 3X2 was never a 70 option but since their installation is in the AIM, GM came close to offering them as an option.
Thanks
Wes
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
Racer
Joined: Nov 2014
Posts: 463
Likes: 129
I have the original 3X2 carbs from my 69. I'm thinking about having them rebuilt to install on the 70 BB. The carbs were working fine when I removed them in the early 1980's. I'm thinking about a rebuild from either Holley or All American Carbs (Florida). I'd like to buy all new if possible. Holley sells new repro 3X2 carbs set up for the Chrysler/Dodge 440 cubic inch cars of the 70's (?) Anyone used these carbs on a Corvette?
Thanks
Thanks
John
Burning Brakes
Joined: Dec 2003
Posts: 1,150
Likes: 154
I have the rect intake(3x2) with oval port heads on my 69 and it runs perfect.The advantage of the 67 intake is the gas lines are farther away from the intake.With the headers it really cooks things under the hood,so if you are o.k. with the l88 hood I'd go with the 67 manifold.
Thread Starter
Team Owner
Joined: Jul 2004
Posts: 40,412
Likes: 792
From: Redondo Beach, California
Thanks for the information. I have aluminum rectangular port heads to match the intake manifold. I'll do the eBay search. I'm hoping Holley still has all the parts to re-build the original 3X2 carbs.
People who have read my posts will recall my story of my 69 with a clone L88 engine in it. The car was stolen. Anyhow, it had rectangular port heads and I drove it both with a rectangular port 3X2 manifold and also with a Holley double pumper manifold with rectangular ports. Supposedly the rectangular ports were not recommended for street use...never had a bit of trouble with engine performance on the street with rectangular ports. ...For people not familiar with BB rectangular ports..each of the 8 ports was about the size of a mid size car's exhaust pipe!
People who have read my posts will recall my story of my 69 with a clone L88 engine in it. The car was stolen. Anyhow, it had rectangular port heads and I drove it both with a rectangular port 3X2 manifold and also with a Holley double pumper manifold with rectangular ports. Supposedly the rectangular ports were not recommended for street use...never had a bit of trouble with engine performance on the street with rectangular ports. ...For people not familiar with BB rectangular ports..each of the 8 ports was about the size of a mid size car's exhaust pipe!
Burning Brakes
Joined: Feb 2012
Posts: 925
Likes: 7
I have the original 3X2 carbs from my 69. I'm thinking about having them rebuilt to install on the 70 BB. The carbs were working fine when I removed them in the early 1980's. I'm thinking about a rebuild from either Holley or All American Carbs (Florida). I'd like to buy all new if possible. Holley sells new repro 3X2 carbs set up for the Chrysler/Dodge 440 cubic inch cars of the 70's (?) Anyone used these carbs on a Corvette?
I think the stock 3X2 69 carbs would flow 350 cubic inches in the outboards and 250 cfm in the center carb. Does anyone know if this is true? I think the Chrysler/Dodge 3X2 carbs were 500 cfm for the outboards and 350 cfm for the center.
If I use the 3X2's on my 70, I do have a 68/69 rectangular port manifold. I also have a 67 rectangular port manifold which I could also use, but I'd have to go to a L88 hood since the 67 manifold has a higher rise.
BTW...the 3X2 carb configuration was never available for the 70 BB's, but the 70 AIM does show a 3X2 carb option for the 70 and has assembly line instructions! Obviously the 3X2 was never a 70 option but since their installation is in the AIM, GM came close to offering them as an option.
Thanks
I think the stock 3X2 69 carbs would flow 350 cubic inches in the outboards and 250 cfm in the center carb. Does anyone know if this is true? I think the Chrysler/Dodge 3X2 carbs were 500 cfm for the outboards and 350 cfm for the center.
If I use the 3X2's on my 70, I do have a 68/69 rectangular port manifold. I also have a 67 rectangular port manifold which I could also use, but I'd have to go to a L88 hood since the 67 manifold has a higher rise.
BTW...the 3X2 carb configuration was never available for the 70 BB's, but the 70 AIM does show a 3X2 carb option for the 70 and has assembly line instructions! Obviously the 3X2 was never a 70 option but since their installation is in the AIM, GM came close to offering them as an option.
Thanks
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