What DaleClark said. On manual cars, the double throttle system is only there to limit engine load during engine warmup by closing the second intake runners.

Check my post here and the following post which has the relevant extract from the FSM: https://www.rx7club.com/rotary-car-p.../#post12300331

The switch point is around 70'C coolant temp. It runs off a solenoid so the double throttle plates are either open or closed.

The presence of the double throttle plates in the secondary runners would limit airflow, but probably not tangibly more than the plates in the throttle body itself.

If you don't like the idea of the double throttles being closed during engine warmup or are worried about them not opening, it would be very easy to rig them in a permanently open position without having to remove them.

 

I don't mind having the double throttle system, it's my new FD did not come with the DT plates so I wanted to make sure what it's function is for exactly. I want this FD to pass the sniffer more easily than my old one so just making sure. Thanks!