Split air pipe
 

Does anyone have any pics of what the split air pipe looks like when connected to the 5th and 6th ports?

The reason I ask, is that the previous owner built a custom exhaust for my car and I'm trying to figure out what he did. To me it looks like there is a bung welded in the downpipe to return (air/pressure) to open the 5th/6th ports, but there also seems to be a hose running from the airpump "T'd" into the return air pipe; this is the part that is confusing me...why would you want to push air both ways through the pipe. I'll work on getting a picture, cause I know this is confusing.

BTW...my actuators work perfectly. My car is also an '87 n/a so the actuators are driven off of exhaust backpressure, not the airpump.

Can anyone help me with this?

It feeds air to the catalytic converter so it can do its job better.

--Gary

I don't have cats...that's why I'm confused. I'll post pics of the exhaust and the split air pipe later today to help clarify a little.

The split air pipe connects to the intake manifold.

About a foot from the intake manifold (memory here) there is a mushroom looking device that is in fact a checkvalve.

Just below this checkvalve and down towards the catalytic converter direction, there is an approx 3/16 pipe that comes off the split air pipe.

That approx 3/16 nipple gets a hose put on it. The other end of that hosse goes to the auxillary port feed pipe. That 3/16 pipe carries exaust gas pressure to open the auxillary ports at approx 5000 rpm.

The mushroom checkvalve keeps exaust gas from entering the intake manifold.

There are no decent pictures in a series four fsm of the arrangement.

The very aft end of the Split Air Pipe connects to a nipple on the catalytic converter.

The only decent way to make the auxillary ports work is to buy a rpm switch from SummitRacing, combine it with a spare solenoid off a RX-7, along with a barbed plastic nipple picking off airpump pressure from the HOSE B/T THE AIRPUMP AND THE ACV. NOT the hose b/t the acv and the silencer in the right front fender.