Hey, I finally got my block off plate from mazdatrix today. I've been searching the forum for anything about rats nest removal for about a week and only came up with:
https://www.rx7club.com/forum/showth...=ACV+block+off
and
https://www.rx7club.com/forum/showth...=ACV+block+off

Are there any links/pages that describe the removal of the rats nest or should I basically just study my Haynes manual religiously?

I have a stock 83 GSL.

If there are not any links could anyone post some tips, or things too watch for/avoid?

Thanks in advance.

 

Are you talking about a actual rats nest under the hood?! I had one in my FC this past summer because it had been sitting for 5years! I went out of the way looking for animal remains there since it was sitting that long, I kinda figure there may be a nest or something were I couldn't see it.

 

Heehee, no I'm sure my previous coolant leak and subsequent(sp?) smoke would have killed any animals living under the hood.
Just asking about removing all the emmissions stuff.

 

i wouldn't mind removing my rats nest too, as well as that pesky bird's nest as well... if ya find anything, post it here!

thanx

 

Its pretty easy. Just unplug all the coloured plugs, pull every hose, remove the 2 hold down bolts and pull. Next cap ALL openings left in the carb spacer. If you still want to run vacuum advance, you can hookup the 2 (1 in early RX's) solenoids minus the railing but I'd recommend forgetting about the vac advance.

 

what good does it do removing the emissions stuff anyways? will I actually gain anything from it? and is it really as simple as just physically removing it and caping off all the open connections? Just wondering (this is a 12A btw)

 

You gain simplicity and by removing the solenoids, you eliminate many controlled air leaks... that's about it. I personaly like the look of the plugs and stuff. When I used a Nikki I still had the rats nest but it wasnt actually doing anything.

 

It's cool to hear ths shutter valve working... let off the throttle and you hear a lil' "Fweeeee!". Nothing like a BOV thank God, (noisy BOVs are just plain tacky IMO).

But the strange bogs and hitches when driving around are quite annoying. It's so nice to have an untouched car, but OTOH stock isn't always very good, especially on late model carbureted cars.

 

I've yet to hear anyone claim a performance improvement, although I've seen some very nice looking engine compartments without the nest.

One thing though, when certain emissions items start to leak air or go bad, that'll certainly hurt your performance. Some guys have removed'em just to avoid those problems.

If they are working correctly, the nest doesn't effect performance since most of it only works during coasting and decelleration. Keeps your car smelling nice for the guys you just passed!

 

I, personally, am doing it so I can try and narrow down any problems I have with the car. That and when rebuilding the carb I found out most of those hoses were in pretty bad shape, so I figured I might as well yank em out and clean things up.

I'll try and document everything when I go through with it, maybe throw a web page together or something to help other people who want too do it (and make it easier for someone too help me if I screw up something =]). I was actually hoping too do it today, but the weather had other plans.

 

The only dillema I had while removing my emissions equipment was, what to do with the two lines coming from the oil filler neck. The neck nipple still has the hose on it, but it's pointed down and has a small pice of foam in the end. I couln't find a breather-type filter that 'SilverRocket' mentioned using, and I've run out of ideas for where to look. The other hose off the intermidiate housing is routed into my air cleaner, let us know how it goes. As for benefits, the car used to spit 2 foot blue fireballs when revved up and down hard in neutral, now a pop from the back is really rare. Now I know alot of you wouldn't think of that as an 'improvement' (I sure as hell didn't when I found out I lost the ) but then I realised I didn't want some cop who isn't aware of rotary tendancies to be poking around under my hood trying to figure out what I rigged up to make it shoot flames. I miss the small pops on decel, 4-7 small blue fireballs our the rear was really intense. Have fun pulling all the 'junk', I know I did.

 

Finally went ahead and pulled all the junk off =]. Ended up using a couple different size caps though (couldn't find any that fit exactly) and couldn't take any pictures. Very Glad I took it off, but I have a couple questions.

I basically just removed all the tubing, and all all the colored stuff and hoses, and plugged everything at the carb (except the oil thing, that's just dangling there untill I decide what too do with it)

Where does the block off plate go? What does it do? I'm probably sounding extremely stupid right now, but I didn't see anywhere that needs it.

Is there anything else I can/should pull off? Anything on the carb, or in other areas besides on the tube rack with multiple colors?

Also is there anywhere I can get the correct size plugs?

P.S. I kinda miss the pops from the back as well.

 

The block off plate is for the Air Control and Check Valve located on the opposite side of the carb from the rat's nest. It may not be apparent to you were it goes because no one bothered to ask you if you were still running the airpump. Once the airpump is removed the ACV is the unit that now serves as a powerful vaccum cleaner, the car won't run too pretty until you undo the 3 nuts remove the unit and replace it with the plate. My car idled at 1500 RPM and backfired just sitting there. So I guess my question is, do you still have your airpump. I don't know if you can just leave it on and foget about the plate, because my air pump was long gone before I played with the rat's nest. But I didn't need the plate because my emisions junk was intact and the AVC was closed, it wan'ts until I pulled all the crap that I realised what the hell the plate did!

I bought a pack of caps from the local auto parts store, 2 bucks for a pack of twenty. I'll go look for the sizes later if you need them.

P.S. Why am I so dammed long-winded, I fall asleep reading my own posts. Dammit.

 

Actually thanks for all the great info. I still have a couple questions.

What do I gain/loose from pulling the air pump? Is it responsible for anything besides emmisions/cold running/pumping stuff into the cat?

If I were too pull it, how hard is it, what complications can come up, and what do I have too do to compensate for it.

P.S. The air pump is the thing below and on the opposite side of the engine than the air conditioner correct? Made by someone like nippon denso or something. It has a belt attached too it and is a bit below the carb (I'm pulling this from memory)?

Does it cause any harm if you do not pull the air pump (I don't really have time too pull it untill friday, but can drive another car if it's harmfull)

Basically I'm looking too pull anything I can right now without detrimental effect, but would like too be prepared so I don't screw anything up.

 

Removing the air pump has no big performance gains, meaning you're not going to free up a magical 26 Hp with it off. It was recommended to me that I gut the insides of it and put it back on so the water pump wouln't suffer belt slippage at high RPM. However I couldn't remove all of the interioir parts so when I put it back on it ran unbalanced and shook itself to death. The pivot bolt mount snapped off, it's only on two bolts so it's not hard to take off. You need to find someone who removed their emissions junk with the air pump still functioning, Silver Rocket may have your answers. All I know is that with the airpump out the ACV was closed most of the time and didn't cause any problems, it made a small whooosing noise like a mini blow off valve, but as soon as I removed the nest it was stuck open and I needed that plate baaad. Hopefully someone who did it in the same order as you will show up and help. I don't know if running without the airpump will damage your cat or not, I never had one. To see the differences look ar page 101 of the Haynes manual for my original system and page 254 for yours, I had it easy compared to you...good luck. -George

 

Or you could just pull the intake manifold off and plug the passage from ACV to intake ports with JB Weld like I did. Who needs a block off plate? Oh yeah you also have to take the engine apart and plug the air injection ports in the exhaust ports... so if you don't want to do that then spend the $10 or whatever on the plate

 

So in order to remove the rats nest, I need to remove the thermal reactor on my 1980 model? Or could I leave the air pump on just for the thermal reactor? Would I need to replace the thermal reactor with headers, or is there a cast iron exhaust manifold for a 12a engine?
Thanks,
Tony

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DO MAKE NOTE:

Do *not* disable the solenoid rack or the air pump if you still have the thermal reactor/heat exchanger installed on the car!

To do otherwise will risk mongo thermal reactor meltdown.