[taff2]

I decided to stick with the proven 'charge pipes entering opposite each other' type of plenum, it seemed to work ok with my old blow through carbs set up.
I basically cut and shut the old carb box, and bolted a pair of 75mm ebay throttle bodies to it- each T/B entering the plenum directly opposite each other for good air distribution. The plenum volume is 396 cu in and it will also have a pair of 2" tall phenolic plastic carb spacers under it which will increase the volume by another 49 cu in, these spacers will house the 160lb injectors, each one aiming down the opposite port ,ie, the number 1 cylinder injector will be opposite at number two cylinder, and so on. I want the fuel injected up high in the manifold for better charge cooling and atomisation.
The box will get the Pontiac arrowhead etched into it and then it will be shot/media blasted so that it has a cast like appearance, not sure if I'm going to paint it Black yet.
There's still quite a bit to do yet, I would like to put a pair of air bells inside the box over the manifold plenums, if I can find something suitable.
I'll post some progress as it's done. We are still going to build an EFI manifold using the Gutsram and Holley top lid we bought for my son's race car, just waiting for them to be delivered.