I have a modified '87 NA RX-7 that has a Bonez cat replacement pipe (which I wouldn't reccomend) and an Apex N1 cat-back exhaust system on it. I've had this car for about 6 months now, and the aux ports have never worked on it, since the Bonez downpipe has nothing on it to operate them. The flange on the downpipe was bent were it connected to the exhaust manifold, so I recently replaced it with a Racing Beat downpipe/pre-silencer which has a tube that comes out of it to operate the aux ports. It is supposed to connect to something that runs up to the aux port actuators, but its not there now. I guess it was removed when the guy i bought it from installed the new exhaust system. I can't find any information about what it looks like or where it goes, so I dont really know how to fix it. Also, the air pump has been removed, but from what I can tell the air pump only starts the ports moving on the S4 cars. Any information about this would be greatly appreciated.

 

Air pump dosent effect the 6th ports on a s4 NA. I used to have the same exhaust setup on my old NA. Bonez race pipe, apex N1 catback. I loved it. My Bonez pipe DID have a piece for the actuation on the ports. It's wierd that yours didn't.

There should be a vaccum hose that goes form your pipe to near the actuators. I can't remeber exactly where though, its been to long.

 

Hmmm, I must have had a different pipe than you. Mine was just a pipe with nothing else. My only problem with it was that the flanges on it werent think enough, so it warped pretty badly where it connected to the manifold. I didn't notice any tube coming off the actuators, either. I might have missed them, but I don't think so. I guess that means its gonna be a pain to redo.

 

If you have a buddy locally with a stock RX-7, you could check his out...or go to a local junk yard to see where its hooked up...
Good luck/skill

 

My S4 has RB presilencer and there is a tube comming from actuators and it goes to the presilencer IIRC. I think an instruction paper came with the presilencer shows it (sorry I don't have it right now)....

 

Unfortuantely, I only know people with TII's, and the town I live in doesn't really have any junk yards to speak of, at least not with RX-7's. The instructions that came with the presilencer were pretty useless. It basically said that once you installed the presilencer, you plugged the tube into the pipe on the presilencer. It gave no specific directions, and had no pictures at all.

 

Here is a pic of my bonez race pipe.

 

The pipe you need is a longer aluminum looking pipe. Its called a split air pipe. Do a search for it and you should find a picture of it on someones car.

13bpower, that brass line coming from your race pipe looks like its made for 1st gen GSL-SEs. My friends header has a connection that looks like that coming from the header and plugs into the intake manifold. FCs split air pipes have flanges instead of a screw on end like the one pictured there.

 

Thanks for the picture. I just went back and looked at the race pipe, and it does have part of that connector. All thats there, though, is the part thats permanately connected to the pipe. The hose isn't there at all. I finally deciphered the stupid diagram in the Haynes manual, so I at least kinda know what to look for in the engine bay. The tube is totally gone, its detatched from the pipe near the actuators. I got ahold of the guy I bought the car from, and I think what happened was that the ports were sticking since the engine had about 215k on it before it finally died, and probably about 190k at the time. He wired the ports open because about all he used it for was racing on road courses where it rarely got below 4-5k RPM. I guess he just totally removed all the stuff needed to operate the aux. ports. Now that I have this figured out, I just need to find something to replace the missing tube. Im probably going to contact Alamo Rotary, where I got the rebuild done, and see if he can get me a replacement. If anyone has ideas on what to use to replace it, I'd love to hear them.

 

https://www.rx7club.com/forum/showth...hreadid=252627

A few posts down is this thread asking what exhaust system the guys car has. It has some good shots of the split air pipe. On the first picture, you can see it coming up next to the downpipe. It looks like the a/c line but you can see that its connected to the lower intake manifold. He also has some shots from under the car where you can clearly see the pipe going into the cat. The stock setup doesnt have clamps and a hose attaching it to the cat. His was modified to accomodate the aftermarket cat. Your car is non turbo so your car will be a little different but these pictures give you a very good idea of what it looks like and where it connects.

 

Thanks for the heads up

 

No, that pipe is for providing air to the cats, it has nothing to do with port actuation. This pipe is run by the Airpump. When you have this race pipe on, the split air pipe is take off and blocked off with a block off plate.

The pipe in my picture is the 86-88 N/A racepipe purchased from rx7.com. I bought in in 2000 and used it for about 2 years.

The actuator pipe for the ports on a s4 N/A is the size of a regular vaccum line and connects to the little piece you seen in my picture.