Rat nest removal from FB
 

Prepping car for future RB headers. The shop manual shows clearly how to removal air pump but I would like a guide to how to remove the rat nest.

Does anyone have this info, or link to old post with this detail.

The link is I the first generation fax section

You can remove it but there really is no need when just installing a header. Ray Green did a study on the rats nest removal and it actually hurt his gas mileage.

if you must, its easy.

unhook vacuum hoses at carb. remove both bolts holding the vacuum assembly to the engine. remove vacuum rack as an assembly. cap ports at carb.

done.

Figured I would remove since air pump will be coming off, the "fat nikki" will be sealed off, can't why I would keep it on. But there are so many lines that I want to make sure not to cause any problems.

if you remove the vacuum rack as an assembly there are 8 vacuum lines, all in a row.

Sorry just follow lines wear they connect to something and cap them off, then remove assembly whole? Well that sound doable. Thanks

If you are keeping the stock catalytic converter, then keeping the air pump is a good idea. It feeds fresh air to the converter and in turn helps to cool the converter. I've seen air pump deletes resulting inmelter converters...

I'm about to put RB headers on a 1984 GSL-SE - do I need to get rid of the air pump?

What you do for the rest of exhaust system after header will determine that..

Well, not really sure my options. I want to keep fairly stock, but I'm wanting a horsepower bump. It will be street use only, so don't want straight pipes. Was considering the 2 RB options, leaning towards the full long, but not sure how loud that would be. Any suggestions?

The RB dual primary system; the one with dual pipes/resonators give best performance of the two from all I have read. I am planning on installing that system next month.

All far as air pump; once you install it on a 12A there is no reason to have air pump. If I get a slipping water pump belt; I plan to install a dual belt system but most people just ran fine with standard belt set-up.

The dual primary is what I'm looking at also, but I'm running a 13b -- does the same apply to that engine as far as the air pump is concerned? I'm assuming yes, since there will be no cats.

If your 13B is GSL-SE that needs back pressure for ports to work then make sure you get the correct RB system (has a pipe in exhaust to allow for the back pressure for the ports) for car. The air pump is for emission and I am pretty sure it can be removed.

You can see the difference between the 13B and 13B GSL-SE system on the RB website.

Unless you are putting a different carb on or you are heavily modifying and/or boosting the Nikki, I would just leave the rats nest in place. If you read through the shop manual, many of those circuits do more than just emissions. They improve cold starts, gas mileage, and smooth out throttle response and deceleration. If you have A/C, it'll boost the idle so the compressor doesn't stall the motor. These are all things you don't need on the race track (which is why many hardcore tuners remove them) but they are nice things to have on the street when you're stuck in traffic. If it ain't broke, why try and fix it? Just remove the air pump and associated piping and leave the nest. If you're itching to do something, maybe grab some colored vacuum line and replace all the dried out lines one by one so you know they are good.

I put this system on my SE last winter,it's expensive,heavy...designed well,should last life of your car. 1st test drive after install you'll see you made a correct choice. You'll have to do a few other steps to insure driveability and reliability.

Thanks again GSLSEforme -- what kind of steps for drive/reliability after the exhaust install?

Rb streetport system is the way to go. Read the info provided on their website,they treat this system as an offroad only mod-no provision given to retain O2 sensor. Some will say to run without it,don't agree,went different way to retain O2 function. Blockoff plate for ACV is necessary, removing air pump likely will cause the waterpump belt to slip from clutch fan drag and not enough grip on remaining belt. Some just tighten the belt... causes premature water pump bearing and eccentric shaft bearing wear. Removal of clutch fan and going to electric fan is an option chosen by lots. I prefer to keep the stock fan as long as working properly,it's well designed and keeps the engine cool as well as or better than most electric fans. A dual alternator pulley to run dual belts is the answer to slippage issues. I can take some pics to show you what it looks like if interested.

MazdaTrix has primary header with O2 sensor port - that's the setup I'm looking at

where did you get your pulley?

The one for the 6 port 13b has the O2 bung, not the 12a. Anyone have a photo of where they placed it, and could I have an exhaust shop install one on the 12a in the same spot down the road when I switch to EFI?

That's the one i'd recommend. It's fairly subdued at idle and lo rpm,gets raspy as aux. ports open in upper rpm band. Civilized at cruising speed. The pulley can be had from several places, i upgraded to hi output FD alternator when i did all the other work so that's not applicable to oe SE alternator. Will look back thru my receipts and get back to you.

Rats nest removal from FB
 

Looks like i sourced a pulley/belts/ tensioner bracket from Banzai Racing,they're a vendor on this site.

chuyler1 - I will be placing a Jeff20B in place of stock Nikki in the future. Not sure how much of rat's nest I will remove yet. I have air and cruise; so I want to make sure they are maintained after swap. Got some one project (making rear fender wells solid) in front of fat nikki, RB exhaust, and dual pulley system.

I'm in the same boat as you. Once I get the exhaust in, I want to start picking through all Jeff20b's mods and do the ones that will let me keep the rats nest and vacuum secondaries (I'm going to try cutting down the spring instead). No plans to boost it.

This is location for oe non heated O2 sensor. If want readings from both rotors,you'll have to install sensor after header is collected and will need to be a heated sensor that far from engine