Read about removing the ports and what it would do good or bad. well decided to wire them open to see if i could notice the less torque at low end and or some gains in high end. well first of all did not have to wire them open because i had to pry them open. they practically did not move. just to confirm..if i remember correctly fully open is at the 6 oclock position?? yes ...no... anyway made them open to the 6 oclock position and well yes they were not opening because i can feel a difference during acceleration. about the low end torque i guess you do loose some. maybe i still dont have them all the way open and dont know for sure what its going to do but one thing is for sure they were not opening so it does afect as far output at higher rpms. gentleman this is only my observations i am not a mechanic nor have i had my rx sevens ( 1st and second gens) for that long. my first gen is carburated so diferent story. if anybody out there has comments please feel free

david

 

Works best if you fix it to run correctly.

 

does s4 have an air pump? i keep seeing mods to open then with airpump on rpm switch but i dont know where it is or what it does/used for? i know s5 uses it to open them already right?

 

Yes, all RX-7s with a cat have air pumps. However the exhaust back pressure opens the aux ports on a 84-88 non turbo 13B.

On the S4 if there are major exhaust leaks or the exhaust has been replaced with a more free flowing design, there will not be sufficent pressure to open the aux ports. This is why you would use the stock air pump and a vacuum switch and RPM switch to activate the aux ports.

And yes, on the S5 (89-91) non turbo, the air pump and a vac switches is/are used by the stock ECU to activate both the aux ports and the S5 VDI system (the latter, the S4 does not have).

 

so IOW, stock ECU is required to run the aux ports on an s5?

 

6 port solenoids are operated by the ECU on s5's... thats where the wire that gets hooked to the solenoid is comming from!!

You can also use the aux outs of a Haltech or Microtech or autec to control them at a set rpm

 

so where is the air pump and what is it used for on an s4