We have on occasion removed the four barrels and replaced them with a Holley 500 2bl. Another good card is the Rocjestor 2 bbl that showed up on some 455 Olds in the early days.A huge carb with good manners and flow. A two barrel seems to run much better on the 6cyl 4bbl manfolds. Now that is espcially true where the carb sits with the primarys forward and the secondaries rearward. IE the Slant six four barrel set up. The difference in drivablilty is remarkable and power is also. No noticeble drop any way. I did this mod first in the 1970s but have recently since seen several chev sixes with it done and for the same reason. Of course the mind goes instantly then (since EFI was mentioned ) how would a Holly Throttle body injection work installed this way. I suspect really good, but I dont really know (yet) The two barrel works better because of the more symetical placement. With the fourbarrel it seeemd one half of the engines run good and the other o so except for full throttle.With the two barrel that is gone comletely and it runs as intended. Course this idea may not suit and that is fine. One should always have what they want on their car , I beleive that. I just offer it from experience. It may not suit you, I understand that especially if your heart wants a four barrel. .
