2 barrel , 4 barrel, whose got the answer?
bear with me please: 1983 318 stock, in a b250 van (concversion). because it is a lean burn (that doesnt work any more) it ios being converted to a hei ignition system with vacuum advance ( the gm hei module). the present carb (2 barrel) doesnt have a vacuum port to run the vacuum advance. so the coice is to either replace the 2 barrel (2280 holley or carter bbd), pull manifoold and change to a 4 barrel, or some combination. in a ideal worl i would change to a spreadbore and run either a thermoquad or quadrajet (550 cfm). since i havent started taking anything apart im open right now to considerations. this will be low rpm use (4500), hoping to gain better mileage (arent we all) as well as more power.
to summereize.\, a stockk two barrel on stock two barrel manifold, a four barrel on that 2 barrel manifold, or a 4 barrel with a 4 barrel manifold.
interested in your thoughts if you please. i also appreciate your time in responding, thanks
palani
What I have done in the past with the leanburn swaps is;
Edelbrock 600cfm electric choke
Edelbrock throttle adapter
OEM (or open) air cleaner,
OEM or Edelbrock intake manifold
OEM or a MoPar Performenace vacuum advance distributor
MoPar Chrome ignition box though any would do well dept the orange ignition box from MoPar. Orange box ignitions from Mancini will do very well.
This is the basic package for the double conversion to move away from the leanburn systems that most always fail and the 2 to 4 barrel conversions.
A wire tap or splice will probably have to be done to use for the electrical choke connection. The auto parts store has these.
The linkage to the transmission will need to be adjusted. A simple nut, bolt and a pair of washers installed in the linkage will work just fine. The difference between the 2 & 4 barrel linkage is off just a little bit BUT will be disastrous if not addressed and reworked.
Sometimes, the carb to intake may need an adapter plate to ether or both help seal the carb to the intake and or raise it up a smidge to clear the intake. Since you will check if this issue is present before you proceed to the swap, this will be an easy thing to do.
This is an easy to do swap and adjustment on the transmission linkage for a great operating transmission. It is NOT HARD TO DO.
Keeping the two barrel carb you have now is st drilling a hole where it needs to be to add a vacuum port.