1-barrel to 2-barrel carb

[gmcdeadhead]

has anyone taken off there 1-barrel carb and replaced it with a rochester 2-barrel carb? if so how was it? gas mileage , better running, ect. thanks.

[benwah]

I'm guessing inline six? I modified a 1 bl slant 6 with a 2 bl carb off a 318. It did have a lot more pep. I also had added electronic ignition and headers. I wasn't going to split the engine open to change the cam, so I didn't add a four barrel. It was just a fun project with some spare parts kicking around the shop. With that said I'd love to find a cheap 235 intake manifold. A few hours a drill press and a Bridgeport, I'll have a nice 2 bl intake.

[TJ's Chevy]

I am running a stock 292 with a 600 Edelbrock, clifford intake and headers and an hei and the motor runs like a dream. lol. Mileage when cruising at 55...probably around 16 ISH. The 292 wasn't the best on milage until you put an over drive on. I used to have a 350 CFM Holley 2 barrel on the 292 and it ran great as well. You'll notice a bigger difference if you convert to headers as well.

[porter90]

do you mean putting the 2bbl on with an adapter or is there a rochester 2bbl that will bolt up? im also trying to find the best option to get rid of my 1bbl.

[gmcdeadhead]

i was asking if anybody took off there 1 barrel carb and put on a 2 barrel carb. ? just wanted to see if anybody did that and if so how was the outcome?

[TJ's Chevy]

Originally Posted by porter90

do you mean putting the 2bbl on with an adapter or is there a rochester 2bbl that will bolt up? im also trying to find the best option to get rid of my 1bbl.

I bought an adapter from Trans adapt which adapts a 2 barrel holley down to a single barrel 194-230-250-292 manifold. It worked fine. What 6 cylinder do you have?

[TJ's Chevy]

Originally Posted by gmcdeadhead

i was asking if anybody took off there 1 barrel carb and put on a 2 barrel carb. ? just wanted to see if anybody did that and if so how was the outcome?

I've done it with my 292 I6 and worked nicely....

[gmcdeadhead]

What 6 cylinder do you have

292 motor

[gmcdeadhead]

I've done it with my 292 I6 and worked nicely....

how well did it work? better gas mileage ? runs better? ect.

[TJ's Chevy]

Originally Posted by gmcdeadhead

how well did it work? better gas mileage ? runs better? ect.

Ran a tad better..easier starts(with HEI) and accelerated a tad better. Slightly better mileage. I used a 350 holley...if I was you i'd do a 500 cfm 2 barrel holley or 500 cfm edelbrock 4 barrel mounted on a clifford intake and add headers. You'' get the best mileage outta a 4 barrel And headers. I probably was getting around 14 and now probably 16.

[T2vigil]

I installed a Webber 32/36 with adaptor on my stock 1 barrel manifold. I also installed Tom Langdons cast iron split headers. The increase in power is very noticeable. I could not be more pleased.

[Former member Yoder213]

I'm looking to do the same, but the split iron headers from Tom Langdon did make a pretty big difference. my 292 right now is getting 11.5 on the highway at 55.

[vin63]

I recently did the conversion on my Pontiac Trophy 4 and it made a night-and-day difference. My Rochester was flighty (running and starting) and I was having to tune it constantly. My mileage hovered inconsistently between 12 mpg - 15 mpg on the freeway (Powerglide), depending on what personality it had that day. After the conversion, the engine starts right up, idles better than ever, and I get a consistent 18 mpg on the freeway. I used a Trans-Dapt adapter and blended the transition by hand. I also used a 2bbl phenolic spacer from Canton Racing Products. I could never get the Rochester to operate as efficiently as the Holley 2bbl, no matter what I tried.

[jayoldschool]

Anyone use a GM Rochester 2BBL? I still have my complete setup sitting around from my 71 Chevy 350 that I upgraded.

[Bowler1]

Does anyone have an update on this thread? I cannot afford to do the complete change to headers and intake but need to do something my one barrel is trash. If I go to transport adapter which carb do I use?

[Bowler1]

Bump

[franken]

Bump doesn't tell us much.
Ect isn't a word or abbreviation just for general info. illiteracy is a bad thing. Try etc.
Ggenerally from GM the carb size is an indication of engine design; or rather compression and cam selection.
A laeger carb may help performance but I'd rebuild the monojet.

[Mike Wessinger]

Originally Posted by franken

Bump doesn't tell us much.
Ect isn't a word or abbreviation just for general info. illiteracy is a bad thing. Try etc.
Ggenerally from GM the carb size is an indication of engine design; or rather compression and cam selection.
A laeger carb may help performance but I'd rebuild the monojet.

"Bump" tells us Bowler1 is still waiting for an answer to his question about which carb to use with the adapter, so he bumped this thread up to the top where it may be seen again, and possibly someone could assist him with the question.

And when you decide to play the role of grammar police on an internet forum, make sure you proof your own post before you submit it.

[aerotruk63]

Originally Posted by Mike Wessinger

"Bump" tells us Bowler1 is still waiting for an answer to his question about which carb to use with the adapter, so he bumped this thread up to the top where it may be seen again, and possibly someone could assist him with the question.

And when you decide to play the role of grammar police on an internet forum, make sure you proof your own post before you submit it.

[old51sedan]

Originally Posted by TJ's Chevy

I am running a stock 292 with a 600 Edelbrock, clifford intake and headers and an hei and the motor runs like a dream. lol. Mileage when cruising at 55...probably around 16 ISH. The 292 wasn't the best on milage until you put an over drive on. I used to have a 350 CFM Holley 2 barrel on the 292 and it ran great as well. You'll notice a bigger difference if you convert to headers as well.

TJ,
I currently have a 292, stock in my truck. I have a set of Langstons headers I would like to install. I'm looking for a Clifford intake and they are sold out, if I don't run across one by spring I plan on adapting a 2 barrel holly to my original intake. My question to you is, I'm only going to drive this in the summer so do you think I need to add heat to the intake? It will probably never run below 55 degrees.

[1971 GMC SHORTY]

I Did Stromberg to 525 Holly so Much Better Pulls Harder And better gas mileage