j_tso

iTrader: (2)

I've been trying for the last few months to get my auxiliary ports to work, but even with the Mazdatrix modified headers they don't work. They only budge a little bit at over 5000 rpm in 2nd gear.

The actuators themselves work. I've tested them with a pump and gauge tee'd into it, they open at around 2 psi and all the way not much higher than that. The pump was connected to the metal pipe that supplies air to both of them. So I'm thinking it's the exhaust pressure getting lost somewhere.

The tube that goes out of the header was not supplied, but I got a 3/16" steel tube hooked up between the two. I flared one end with the tube nut that goes into the header, and bubble flared the other one that goes into the vacuum hose between the actuator side.

I know I'm missing something. Should the pipe be bent 90 degrees like in the photo on the site? Teflon tape on the tube nut? The header has a new metal gasket, so I don't think there's a leak there.

Ideas, anyone?

The rest of the exhaust is the Racing Beat dual presilencers (for 12A) and muffler. The car is a first gen RX with a S4 13B.
This is the header I'm talking about Scroll halfway down.

Ted Webster

Are you using the air pump for any of the supplied pressure?, or trying to actuate them with the exhaust alone?

I tried that setup when I installed my RB street header with Apexi N1 dual and it worked about like what you are describing. I ended up using the air pump and exhaust to supply mine with a dump orifice to unload the excess pressure of the air pump. Now they come in at 3800 rpm and full open by 5K. I made the setup using simple copper plumbing parts. It sounds a little strange but it works very well, and is very reliable---no motorized parts other than the air pump. I imagine if the dumped air was routed to the bottom of the car using a larger diameter hose it would really help nulify the air noise.

j_tso

iTrader: (2)

I'm just using the exhaust. The air pump is still there, just not hooked up to anything.

could you describe your set up a little more?

SecondGenPat

if you have taken the air control valve off and blocked it you will not get any exhaust to the actuators.
If the ACV is still there it may be carbonized of damaged and not allowing exhaust to flow.

For Block-off plate:
You will need some gasket material
Start off by making 2-3 layers in the outline of the plate/ACV
Now, look at your lim, you will need to cut out a "port" in all the layers of your gasket, from the round hole (where the check valve rest) to that other rough port (kinda looks like long island, NY) But do not cut the port too big that there is too little of an outer edge.
you do not need to cut your "port" as big as the casting holes, it can be smaller, we're not looking for flow, just pressure.

RotaryRocket88

iTrader: (7)

No. The ACV has nothing to do with the aux. port actuators. The exhaust pressure source comes directly off the side of the split air pipe, before it gets anywhere near the ACV. What it sounds like you're talking about is tapping into the port air path from where the ACV used to sit. There's no point in doing that, since the existing split air source (or header source in this case) does the same thing.

In my experience, using exhaust pressure to control the actuators is hit and miss. I went another route when I had my NA engine. 1 Summit RPM switch + 1 emissions solenoid + a nipple tapped / welded into the back of the air pump leads to a very stable setup. Air pressure from the pump is directed to the solenoid, which is then set to trigger at 3800 RPM via the switch. Air flows to the actuators, and they open exactly like they do on an S5 NA engine.

The only other thing to consider is how to prevent the air pump from reducing pressure through the normal ~3/4" opening. When I did it, I had the ACV in place, and used a plug in the dump path with a small hole in it. This kept overall pressure high enough (>~2 psi) to open the ports. If you have no ACV, you could just plug the air pump's output directly. It has a pressure relief opening on the back already.

FelixIsGod29X

iTrader: (50)

The actuators may work fine but does the rod that goes through the LIM to the aux sleeves move 100% freely? I recently found a s4 na lim in my attic. If came off a low compression s4 na. One rod moves easy as pie the other one is stuck as can be.

walken

iTrader: (6)

do you have new gaskets on the actuators? I hit them and the lim up with a wirewheel and they functioned correctly there after. a little silicone spray on the rods might not hurt either.

j_tso

iTrader: (2)

the rods in the LIM move very easily, new gaskets on the actuators as well.

When I said I tested them with a pump, I mean the pump was hooked up to the inlet on the LIM, and both opened fully. The pump was a cheapo hand pump like the ones used to inflate pool toys, and hardly took any effort to open them.

SecondGenPat

If you follow the split air pipe closer to the intake from where the actuator nipple is you will see a large metal piece in-line with the split air pipe, this is a one way check valve for exhaust. Keep following because right after this valve the split air pipe becomes a rubber hose, this hose is clamped to the lim. Where it connects to the lim is the exhaust source for the 6 port actuators. Now let me explain:

The lim has the 4 intake port casting (obviously) but it also hides 2 exhaust port castings. The exhaust from the end irons is routed up from the main exhaust ports through the end irons via a cast-in channel and exits below the intake ports into the lim. (this channel has been previously discussed here as something to seal up on a rebuild via TitainiumTT I believe)
From there, the exhaust gasses are routed to that circular check valve in the lim that sits beneath the ACV, through the ACV and back into the lim through that "rough" cast-in port. Then the exhaust gasses are routed through the lim to the split air pipe nipple that connects to the rubber hose as previously mentioned.

I do know what I'm talking about as this past winter I "refreshed" my intake assembly on my 1987 base for which I am the second owner still on the factory clutch and the only modifications I have done: are EGR block-off, smog pump/ACV removal, rats nest removal, and secondary throttle plate delete. After my "refresh" I noticed my 6 ports were not working, It took me 3 days and 4 discussions with a Mazda master tech from back in the RX-7's hayday to figure this issue out.

However, I do like your solution to the 6 port actuation after emissions delete. Simple and effective. Unless the smog pump is outputting too much pressure and slowly stressing the actuators.

-Pat

j_tso

iTrader: (2)

I thought the one way one valve only lets out air from the air pump (through the ACV) to the cat, so it just prevents the back pressure from the cat's side to getting into the LIM. The back pressure just exits the nipple on the split air pipe to the actuators.

And the exhaust connections through the irons and LIM are for Port Air Valve on the ACV. Air Pump air is directed through that part of the ACV to those ports to lower exhaust temps and clean up emissions.
From Section 4 of the FC3S training manuals

RotaryRocket88

iTrader: (7)

This is correct ^.

2ndgenPat, you're mixing up the air path(s) with the exhaust path. The path behind the check valve you mentioned is called the 'port air path', which is actually separate from the 'split air path'. I took apart a spare ACV one day to get it all straight. The check valve prevents exhaust gases from entering the ACV, while allowing air from the air pump to be directed into the exhaust ports for emissions.

The split air path is separate. The split air solenoid on the ACV opens when in 5th gear only (but the passage is still always partly open) to direct air from the air pump to the back of the LIM & the large nipple you mentioned, past the other check valve (in the metal diaphram), into the split air pipe, then finally into the main catalytic converter.

The S4 actuators operate via exhaust pressure created between the cat and the check valve in the split air pipe. Above 3500 RPM, the relief valve in the ACV actually switches to dump all air from the air pump through the air chamber and silencer to open air, so both of the check valves mentioned will be completely sealed. The entire ACV/LIM/exhaust port area becomes isolated from the split air pipe and the nipple for the aux. port actuators.



source: http://mazdarx7.iougs.com/emissions.shtml