The Holley 500 cfm  $300 2 barrel seems to be it
if a way can be found to lean it. There are several options
out there for that.

The main problems are it must be mounted vertically and the height
is rather high so getting it under the cowl is a challenge.
This is one way I have come up with that still gives the right length
tuned intake pipes for an RX8 P-port engine. HP should be well over
200 at 7500 RPM.

This should be quick to build and straight forward to install. Could save as
much as a year compared to electronic solutions.

Paul Lamar

Paul

On that last pic, draw the flat slide assembly sitting on top of the box
as opposes to the butterfly valve. or will that not work?

Tony

I think you are referring to this one. It is kind of interesting
that the RX8 p-port does not need a slide throttle or butterflies
located in the rotor housings because it is a side exhaust with
a peripheral intake configuration. It idles as well as any
Mazda rotary engine built up to the RX8. The roles of the p-port are
reversed. Side-exhaust p-port-intake rather than side-intake
p-port-exhaust. As far as power generation is concerned it is far more
important to use a p-port intake compared to a p-port exhaust.
This is due to the modest pressure difference across the intake
port.

So the answer is; the slide is not needed however the butterflies
in the carb cause a bit of power loss due to their aerodynamic drag.

Well then yes a slide throttle under the carb replacing
the butterflies might work but it is a major revision
that would up the cost. You might as well use two 48 mm slide
throttle Mikuni's mounted on the end of the runners. The height
savings would be in favor of the Mikuni's.

Paul Lamar