318 - I think I need a 4 barrel

[Glennster]

We tinkered , but can't get rid of the hesitation on my 1970 318. I've got the original Carter 2 barrel on it, I've heard that those carbs can be a pain as far as the hesitation goes.
  I'm thinking I ought to put a new intake and a 4 barrel on it to smooth it out.
What would be a good carb and intake for this??? I'm not trying to make it go fast, I just want to get smoother more responsive acceleration.
Anybody got a set up to sell?
THANKS!

[DoNotChallengeHer]

I have a factory dual plane and a Eldebrock 600 cfm on my 318. It works great , I love it.   

[hemiken]

  this would be a good combo for a 318

[67vertman]

We tinkered , but can't get rid of the hesitation on my 1970 318. I've got the original Carter 2 barrel on it, I've heard that those carbs can be a pain as far as the hesitation goes.

I am working on the same thing.    Mine stumbles off idle, and I will be trying to work it out again today.      I too, have been thinking of going with a four barrel, so thanks all for the information on what works.

[DoNotChallengeHer]

 They will stumble with a single plane intake.

[bb71challenger]

I changed my original 2 barrel to a factory 4 barrel intake and small holley 600 double pumper and it made all the difference in the world. I could actually power brake my car and do a really nice burnout. Thats with 3.23 sure grip gears too. You will definitely like the difference it makes but make sure you keep the original intake/carb/air cleaner just because its the original equipment.

[sloop]

im using a edelbrook performer w/ 600 holly vac sec on my car and seems to run fine.  I would dare to guess about a 30hp increase.  My car currently has the orir 2.76:1 and gets about 17 mpg around town

[Super Blue 72]

I know, I'm  but on a 318 I had I took off the 2 barrel and put a Weiand dual plane intake with a Rochester Quadrajet because I liked the smaller primaries and it was what I had in the garage at the time.  Worked well, really good top end, not sure the CFM rating but it may have been a tad over carbed but no bog off the line.

[sloop]

i may be wrong but i think all q jets are the same cfm rating... heard that somwhere...

[acudanut]

I changed my original 2 barrel to a factory 4 barrel intake and small holley 600 double pumper and it made all the difference in the world. I could actually power brake my car and do a really nice burnout. Thats with 3.23 sure grip gears too. You will definitely like the difference it makes but make sure you keep the original intake/carb/air cleaner just because its the original equipment.

I agree.  It solved my problem and gave me more HP.
I junked my intake/carb/air cleaner, because I could care a less about little stuff like that. AND because it is only a 318, not a 426 Hemi.

[bb71challenger]

I agree.  It solved my problem and gave me more HP.
I junked my intake/carb/air cleaner, because I could care a less about little stuff like that. AND because it is only a 318, not a 426 Hemi.

LOL to be honest I stuck my intake/carb/air cleaner in the corner of my backyard for about 13 years. I think I threw it away last year or else it is still there so I kind of agree with you but if its possible its nice to have the original stuff on a car like his.

[sloop]

i still have my intake and carb... if anyone of you would care to donate a 2bbl air cleaner, i would love to have it

[bb71challenger]

i still have my intake and carb... if anyone of you would care to donate a 2bbl air cleaner, i would love to have it

I just used my little keychain led light and walked out to the corner of my yard. I did not throw the intake setup away so if you want the air cleaner its yours. I have an air cleaner on the way and when it gets here I will put the 2 barrel cleaner in there and even the carb if you want it for a rebuild core. Shoot me a pm with your shipping address.

[Super Blue 72]

i may be wrong but i think all q jets are the same cfm rating... heard that somwhere...

I think you're right.  I don't understand why but for a SB V8, of course depending upon how it's built, let's say mild, most would recommend 600-650cfm.  But the Q-Jet and T-Quad are rated at like 750-800cfm.... I wonder if it's because of the smaller primaries?   



The change from the 2 barrel setup to the 4 barrel set up on my car was BIG.  Not only off the line but top end.

Not a performance car, but it was a 1982 5th Ave, 318, 2 barrel Lean Burn system.  I used to drive up to Montreal and on some of the highways in Vermont you could really open up the car.   

I literally had the pedal to the floor and a VW Rabbit buzzed by me.    The speedo only went up to 85mph but I couldn't have been doing much more than that.

After I put on the Weiand DP, Q-jet, and modded the exhaust, I trailed a mid 80's Trans Am and when we got off the highway I asked him how fast we were going and he said 105mph and I still had about 1-2" more pedal travel. 

[femtnmax]

They will stumble with a single plane intake.

  The single plane intake with their large plenum area equals a weaker vacuum signal to the carb, which would easily explain the stumble on acceleration.  Notice the quadrajet and thermoquads have extra small primary throttle plates, and dual venturies within the primaries to provide a strong vacuum signal.  This means better throttle response and better fuel economy.    The single plane with its weak carb signal means POOR fuel economy.  I would never suggest running a single plane intake on a street engine, even though mopar used them OEM on some 318's etc.  Doesn't matter, its still a bad idea.  Dual plane=torque, and torque is KING on the street.