2 barrel to 4 barrel?

[jukebox hero]

Hello, im new to this thread so bare with me if i posted in the wrong spot. I just recently bought a '70 firebird 350, turbo 350, and what i belive is a 2.41 (whatever it was stock 2.something). The car is completely stock, and i was thinking about putting on a holley 4 (600cfm) on it. The carb has been sitting around for months and its not getting used so i figured id rebuild it and replace the stock 2brl. I was just wondering if its a good idea. If its just gonna bolt on and not make any difference then i dont want to do it. What do you think?

[Zboner]

for a 350 the best application would be a 600 or 650 CFM, you will need to buy a New Intake Manifold if you want to put the 4 barrel on

[x-40oz-x]

You gotta change the intake first.
and yea it's a good idea.:yup:

[x-40oz-x]

for a 350 the best application would be a 600 or 650 CFM, you will need to buy a New Intake Manifold if you want to put the 4 barrel on
you beat me by about 3 seconds.

[Zboner]

yes, haha i have nothing else to do, lol`

[x-40oz-x]

same here:sillyme:

:lmao:

[jukebox hero]

Hmm, maybe ill buy an intake manifold. When i bought the car, the guy selling it suggested that i get exhaust (headers etc.) because the stock one is restrictive. Also he said that i should change out the distributer for a newer one that i could get on 74(?) GM v8s and up. If i do that i figure ill buy new plugs and wires.
Im just looking for a few quick bolt ons, i dont want to spend any real money, because i rarely see any significant difference in performance with bolt ons. One day ill put some work into performance, but for now im working on interior and rust problems. When i build for performance i figure ill do a rebuild.
On top of that i dont know how tired this motor is, i havent checked compression or anything yet. It is pretty clean though, literally, theres not much old oil/greese/dirt/etc on the block. The oil is pretty clean, but i havent really checked anything yet.

[x-40oz-x]

You really should do the exhaust before the intake.or else your just making it even more restrictive.
If it were mine the first thing i'd do is new plugs and wires.

[snaggeltooth]

get a old Pontiac 4 barrel and put on a Rochester ... You will see a world of diff..

[69 Custom S Vert]

PY's catalogue lists a 2bbl fuel pump and a 4bbl fuel pump. Do you have to switch pumps when switching from a 2 bb; carb to a 4 bbl?

[69 Custom S Vert]

Check out this site for anything pontiac including 350 builds:

performanceyears.com

[05gtoautoX]

a 4bbl fuel pump flowed very little more than a 2bbl fuel pump, but depending on the condition of the current one it might not hurt to replace/upgrade it, but I wouldn't worry about it, change your plugs/wires, upgrade distributor to H.E.I. (D.U.I.-MSD, ACCEL, or just a stock delco-remy) buy a edelbrock performer/RPM depending on hood clearances, holley 600/650cfm carb. and a set of headers(hooker,thorley, hedman, flowtech etc.) all this can be had for about 600-700$ and I guarantee you, you will feel the difference, also all this can be saved for when you rebuild it, probably not wanting to spend that much but that is the order I would do it in.