So I am thinking of installed the RB exhaust system (header, presilencer, muffler...part of the install is removing the air pump. With the air pump removed, am I forced to remove the rats nest as well?

 

nope! you're not even required to remove the air pump

 

I was going by the .pdf directions that come with the system from RB...see below...are the instructions wrong? I am really ignorant on this, so any help would be appreciated!!! I have a 85 GSL manual transmission

NOTE: We recommend the use of “High Temperature” silicone sealant on all exhaust joints. However, the use of this material is not required.
1. Remove the air pump, belt and bracket, the exhaust manifold and heat shield. Then remove the pipe that extended down to the catalytic converter, and the converter itself. Remove the small tube that connects the intake manifold to the catalytic converter, and the valve on the side of the intake manifold nearest the right fender well (held on by three (3) nuts). NOTE: At this point, if you are planning to use the original air filter housing, tape shut, plug or crimp the two (2) small blue tubes on that housing which step one (1) uncovers.
2. Install the header and muffler, with the nut or bracket on the side of the muffler toward the front and toward the center line of the car. To reduce the chance of gasket leakage, tighten the nuts/bolts gradually in several small steps. In the case of the nuts that hold the header to the engine, tighten the lower nuts first in each step.
3. (1981-83 only) Attach one end of the strap supplied to this side of the muffler with the bolt and lock washer supplied. Connect the other end of the strap to the bracket on the transmission with the original bolt. (1984 only) Attach the muffler to the original rubber mount.
4. Remove the three (3) studs that held the valve to the side of the intake manifold. Use the triangular cover plate and three (3) screws to cover the opening on the intake manifold (be sure to use the original green gasket and some gasket sealer). NOTE: Check all heat shields to ensure a minimum of 1/2” clearance around the header system.

 

you don't have to remove the ACV if you don't want to, and the instructions don't say anything about the rats nest

 

Understand...was thinking if I am removing the air pumps and blocking off other stuff that goes to the CAT, is it best to remove the nest as well...

 

You mention that you're kinda new to this, so here's the short of it regarding Racing Beat exhaust setup.

First off, if you have emissions testing in your locale, you might want to consider leaving much of the emissions controls in place, including the Air Pump and Rats Nest components. As above, these aren't necessary to be removed, and will cause problems of their own, as the rats nest was designed by Mazda to prevent backfiring on deceleration, improve ignition timing under acceleration and under load, and various other small things which add up to a smooth running car. The header can be installed and the Air Pump belt removed to reduce complexity, but there's no performance gain in doing so. The biggest benefit of the header is removal of the constriction due to catalysts which lets the exhaust out more quickly and uncorks the engine considerably. The other side benefit is reduced underhood temps with a weight savings as well.

Many guys here have removed the rats nest only to reinstall it later, as the car drives horrendously on the street without these systems in play. If Mazda thought they weren't needed, they would have saved million$ by not installing them to begin with. It's all there for a reason, and good reasons if your city or county has emissions testing that you'll eventually be subject to following.

 

LongDuck,

I really don't want to remove the nest...mine actually looks pretty good at this point with the multi colored vacuum lines... :0) . And the car is running great. I know my ignorance is showing, but that is why I am on here...Florida has no emissions testing so that is not an issue. I would like to install the entire RB exhaust system (header, muffler, pre-silencer). It is my understanding that there are a couple of connections at the CAT that feed into the whole system. With those blocked off, will it effect the system? That is why I was thinking that removing the nest would be more or less required. Now, after what I have read, once I get the headers on I can reinstall all of the emissions stuff, including air pump, but must put blank off plates/caps for those item with inputs from the CAT. Is that correct?

 

so....among a bunch of other stuff I have completed (new aluminum radiator, water pump, cleaned up and painted water pump housing, dual pulleys on my alternator, etc....) I have removed the air pump and the ACV. I am going to leave the rats nest alone and use blank off plates. I don't see the bolts/nuts holding on the upper half of the heat shield...but I will find them...unless anyone has some pics....

Ordered my RB exhaust system, looks like it won't be here until early sept. That's OK, gives me time to pull the manifold and the exhaust parts and time to soak down the bolts/nuts in Kroil.

 

You don't have to reinstall it if you just don't remove it. Leave that stuff on there if you like the way it drives today.

The connections for the air pump will be obvious, and you don't need block off plates if you leave it all intact. I drive an SE, and ran with a working air pump and RB header for decades, with working 5&6 ports, too.

 

My intention is to leave the pump and acv off...hoping it won't affect how it runs now...obviously keeping everything including hardware in case I want to reinstall. Any recommendations?