what do you do with the split air tube when you go with a straight pipe?????? i have a n/a 87 and i just recently put the straight pipe in...i've read that it controls the 5th and 6th port, what affect will it have if its not hooked up???

 

split air tube sends exhaust gas back towards the aux. ports to create the psi they need to open. think of it as artificial back pressure

 

Well if you have a straigh pipe you can wire them or find some other way to operate them. I would dish out the cash for a pre-silencer, that would probably help a lot with building the backpressure to make the ports work.

 

Your ports wont open up if you remove it..

Time to figure out another way...

Jarrett

 

If you have a standalone it shouldn't be hard to figure something out to make them work. The TECIII has I belive 2 auxiliary channels to make it do whatever you want. Hook up some solenoids on one of those and have it open em up at whatever RPM you want.

 

You know, you can keep the stock air pump and use that to control the aux. ports. Just run a line off the outlet on the pump to the aux port line and put a valve in between so that you can adjust where the ports open. I would draw you a picture, but Im too lazy right now.

 

When did I insult anyone? A presilencer is just a straight-through muffler, there's very little restriction in them. You still need a source of pressure to operate the actuators, which means either exhaust backpressure or an air pump. A standalone is overkill just for this, because a cheap rpm switch will do the same job. Yeah, but everyone wants to ditch the air pump! You're right though; the stock air pump, a solenoid valve and an rpm switch are all you need to make a fully functioning, tuneable 6PI system. Electric air pumps get suggested too, but I'd check the current draw on those before I put one near the FC's electrical system.

 

Originally posted by NZConvertible
When did I insult anyone? A presilencer is just a straight-through muffler, there's very little restriction in them. You still need a source of pressure to operate the actuators, which means either exhaust backpressure or an air pump.


Uh go to the RB site. The large pre-silencer they sell is specifically designed to give enough backpressure to open up the ports it also comes with a fitting for the split air tube if you did not know in your hundred years of knowledge. See for your self and then tell me I don't know what I am talking about. My friend has that pre-silencer along with the RB headers.

 

it just sounds like you don't know what you're talking about.


Insult to me sir. and Just because I am imature does not mean I don't know what I am talking about so I suggest you cool it because not one person on this thread didn't know what he was talking about when he(and I) said 5th and 6th ports.

 

First - Mazda calls them "auxiliary ports" and they are part of the "6-port induction system."

Second - Kevin at RotaryResurection.com wrote up this simple, elegant way to work the S4 aux ports from the air pump.

Airpump 6pi actuation:
Basically you're gonna get some aquarium parts for this a brass part that joins 2 airline hoses together (union) is used to tap into the air pump supply. Use a small drillbit to make a pilot hole in the hose exiting the rear of the air pump, and insert your brass tap with hose (vacuum hose) on it. You're gonna get an aquarium air valve, one with 1 inlet and 2 valves/outlets on it. Ill explain why in a minute.

Run your airpump supply to the inlet of this valve. Run more hose from one of the outlets to the 6PI nipple on the motor. Open this valve about halfway, and the other about halfway, open-air vented. The reason you must vent/dump some air constantly is because the airpump is always generating some pressure. Since the 6pi system is (supposed to be) airtight, once theyre pressurized (open), they wont want to return shutsince the airpump is still spinning some pressure on them...having an air dump allows the pressure to bleed quicker and allows them to shut more normally.

IT WILL take some adjustments of both valves to obtain a decent working setup. Opening the 6pi valve more makes them open quicker, and opening the dump valve more makes them close quicker, though having them both too far open makes neither work well...it'll take you 20-30 minutes of playing around to get it decent. Grab the throttle and rev the car up to see what happens with each adjustment. You want them to open fairly quickly (1-2 seconds) after reaching 3500-4000rpm, and close fairly quickly (2-3 seconds) after releasing the throttle. You can never obtain a fast/precise operation this way, but it's cheap and a lot better than relying on your exhaust to do the job. IT's also better because you can open them in neutral (as opposed to only under load) and watch what happens for testing/adjustment, and the actuation will be the same in all gears (air pump rpm, not exhaust backpressure).

 

actually with the Series 4 there are 2 actuators that run on exhaust back pressure that then turn a sleve that acts as a valve opening the 2 aux ports

 

You are correct, but if you change to a free flowing (low back pressure) exhaust, you have to come up with an alternate method.

 

I know the RB site and their products well. I also know what a presilenser actually looks like inside, and how much restriction they actually cause. Read more carefully. I never said you don't know what you're talking about. I think you need to harden up a little.

 

That's a nice simple method, but I'd prefer the precision of an electric solenoid valve. The rpm switch is easily adjusted to the rpm you want, and if you use one of your leftover stock emissions solenoids, the venting problem goes away, because those are 3-port valves. The little filter thing on the end is the dump to atmosphere.