A couple of years ago, i got an idea for an experimental mod for nailhead engines.... Since there are no single 4 high performance intake manifolds for the 1953 thru 1966 engines , I was turning this problem over in my mind and decided to do an experiment,,,, I removed the intake off my 64 rivs 425 engine and using a tungston carbide burr and a cut off wheel and a saws all,,, I port matched the intake ports to the head manifold gaskets and then I cut the dividers from between the FRONT and REAR barrels and LEFT THE CENTER DIVIDER IN.....Then I took my porting kit and the carbide burr and smoothed the cuts up real good ....The idea was to get better breathing on the intake, if the engine wanted it,,,, the whole thing cost me about $4 for sawsall blades....
I made no other changes what so ever.... nothing,,,, and put it back on the engine....same carb [afb] and same air cleaner....
There was a very good increase in power from start ,all the way thru the power band....i was amazed.... and also thought ,,, ''Why didn't Buick do that'...'
Since then several guys from another Buick site have done the same mod and it has caught on and even been given the monicker ''the Doc dual plane",,,,by them...
Just thought I would share,,,,