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Discussion Starter #1 (Edited)
Ok gang. I decided to start a thread about what's needed, not needed, what can get pitched and what must stay as far as the vacuum spaghetti goes under the hood. The guinea pig is my 87 DX. All you Si guys, I'm not sure how much of this will apply to you. But I'm sure it'll at least help. Anyways, I'll update this as often as possible to keep you guys informed of my progress with the spaghetti removal.....

And remember, I'm not responsible for anyone screwin up their car by following what I did. And smog-test takers, you guys will probably just have to wonder how much this might help your car instead of actually doing it... LOL ;)

All vacuum line numbers I refer to are how they are numbered from the factory (or at least as far as I know...all my line numbers correspond with the manuals I've seen anyways...).

First thing I did was ditch the EGR. Emissions crap. Unplug lines #4 and #5 coming from the black box of death (right side of engine bay on firewall) where they meet the metal lines on the engine. Plug off the metal lines. You can also open up the black box and remove the vacuum switches/solenoids that those lines went to, or just cut off the rubber lines where they go into the box. Then you can leave the EGR valve there if you want, or you can make a block-off plate to tidy it up a bit. Also you can remove the EGR tube going to (coming from) the exhaust manifold to the intake. A plug will have to be made for the exhaust manifold, and if you do the block-off plate you may need a plug made for the intake side as well.
6/1/08 -- I did some removal of goods in the black box of death. If you crack open the box you will find a myriad of vacuum switches, check valves, an air filter, etc. etc. At the bottom inside the box is a large aluminum double valve. That's for the EGR and can be taken out of the box and tossed. At this point you can also get rid of the vacuum switches and air filter that are connected to the aluminum valve assembly. Two of the vacuum switches have a single wire going to them. Chop the wire on each of the switches and yank them out. Then you can reassemble the box and reinstall.
Stuff from the black box...



Now, see the black box next to the upper timing cover? And the big hose going from it to the black box sitting on the intake? Get rid of all of it. Both black boxes and the associated large tubes. I kept the tube that runs from the box at the timing cover to the air cleaner assembly and plugged it off. The smaller lines just trim back and plug however you see fit that appeals to your eyes. The aluminum piece connected to the second black box (the one on the intake manifold) I haven't taken off yet so I don't know if there's any holes to plug from taking that piece off. But the large tube from that piece to the exhaust manifold can be removed also and both ends plugged. A plug at the intake-side of that tube may not be necessary, I'm not sure yet since I haven't taken that tube off as of yet.
6/1/08 -- You can also remove the white vacuum switch by the left side of the air cleaner assembly and plug the line going to the metal vacuum lines and also plug the other large line going to the air cleaner. Since the two air chamber boxes (the one on the intake and the one next to the upper timing cover) are gone, that vacuum switch is not needed either.
Stuff from the 2 black boxes on intake and next to timing cover...


Another thing you can toss in the garbage is the Anti-Afterburn Valve. Unplug the vacuum line from the AAB Valve to the metal vacuum line and plug the metal line. Then trim back the smaller lines, plug them off and toss the valve. Not needed for function of the carburetors. All it does is hold the throttle partially open when shifting.

I'll add more to this as I do them. I'll also try to get some pics posted so you guys can see exactly what I'm talking about and where. I'm only putting in the removal of stuff that doesn't adversely affect the performance/driveability of my own car. If it makes my car run like dog$&%t, then I hook it back up and consider it a needful thing to have on there... ;)

6/1/08 -- Control box #2 located on the left strut tower...yank it off and throw it and the vacuum canisters connected to it (one below the power steering reservoir, the other is under the left headlight). Then you can plug off the lines at the metal end. You can also get rid of the little orange vacuum switch connected to it lower down on the strut tower. There's another vacuum switch with three vacuum lines on top of the strut tower. That one needs to stay, but the one vacuum line can be redone so it's just a single line--not split off to elsewhere.
Control box #2 and attatched stuff...


The vacuum line that needed to be redone...


The only good use for Autolite plugs per my past experiences...
 

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Discussion Starter #3
Bump for adding pics finally... hehe ;)
 

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Vacuum crap

Oh the joys of having a U.K. polluting machine with none of that crap on my car from standard oh yay oh yay!!!!

P.S. if anyone needs a close up of my engine bay to see what it's like without any rubbish let me know i'll send you one. Also have a couple of inlet manifolds without the holes and emiision rubbish on if anyone whats one they can have but they'll have to pay shipping etc from U.K.!!!
 

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Discussion Starter #6
Oh the joys of having a U.K. polluting machine with none of that crap on my car from standard oh yay oh yay!!!!

P.S. if anyone needs a close up of my engine bay to see what it's like without any rubbish let me know i'll send you one. Also have a couple of inlet manifolds without the holes and emiision rubbish on if anyone whats one they can have but they'll have to pay shipping etc from U.K.!!!
Hey Rich! Wanna post up those pics on here anyways? I can't speak for everyone, but I know I'd REALLY like to see the underhood of yours since it is already lacking the pollution control crap that our USDM Ludes all have... ;)
 

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Discussion Starter #7 (Edited)
Another couple things that can be rid of on our cars is Frequency Solenoid Valve A and Air Control Valve A. Both are located next to each other on the right side just behind the valve cover. The solenoid valve is the black round valve with clear top and green wire connector with 2 vacuum lines going to it (pretty good sized ones too). The Air Control Valve A is the white plastic valve that is connected to the solenoid valve. Both can be tossed and the resulting lines capped off...not needed...I'll try to get a pic of them and their location tomorrow for you guys! :)

Frequency Solenoid Valve A....


Air Control Valve A....


And the two hooked together by the factory vacuum lines as they sit behind the valve cover on the right side.....


It's raining so I haven't gotten the pic of where exactly they sit under the hood....
 

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Wow very nice indeed. I'll sticky it.
 

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Discussion Starter #11
Very nice! I'm diggin the Webers man! ;) Got any more pics of the middle one from a couple other angles? I'm already getting ideas for more stuff to come off...(next is the vapor cannister/lines)...
 

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o man y couldnt u do one for si. i know u dont have one but damn
 

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Discussion Starter #13
o man y couldnt u do one for si. i know u dont have one but damn
If I had one I would man! Maybe someday I'll be lucky enough to find a Si that's in my price range (cheap lol)... ;)

Update time! The entire black box and it's contents can be ripped out and chucked! All you need to do is a little vacuum line reworking. The power valve can be hooked to manifold vacuum as well as both of the vacuum advance lines. The advance I actually hooked together with a t-fitting and ran that to manifold vacuum. Seems to be working just fine for me! The power valve also needs to run to manifold vacuum and tomorrow I'll try to get some pics of which line needs to be run to vacuum and where I ran it to. Also, the valve on the driver's strut tower (with 3 vacuum lines to it) can also be pulled off. One of those lines needs to be capped off (#22 on factory lines at the carbs), the other two I also capped off. Those two I want to do a little more investigating into as far as whether they should be going to ported vacuum or not... ;)
 

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you sir are fucking awsome!!! i shall begin my quest on monday so if you have or already have had any tragic errors or oh shit can't pull that moments please let me know..i'm gonna use this as a manual!!
 

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I began mine a while back, but I tackled the black box two days ago ... I even dismantled the box and have just attached what was left to the firewall...


One question. What can be done with the charcoal canister? (that IS the charcoal canister next to the firewall, right?) I don't need it, correct? If not, then the only lines remaining from the black box should be for the vacuum advance on the ditsro...can anyone confirm or deny this please?
 

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Discussion Starter #17
You can get rid of the canister, but you'll be smelling gas in your car if you do. I found that one out the hard way. It basically collects the fuel vapors from the tank and burns them as you're driving.
I got rid of the canister also, but I haven't had any problems of smelling gas at all since then. I left the line going to the firewall from the canister open for a vent for the tank. So far, so good! ;) I also did a little reworking of the lines remaining. Lines #23, 24, and 25 (the 3 that went to the valve on the left strut tower) I originally capped off separately. Now, I've hooked the three together with a t-fitting and it's running like a champ! So as of now, I've basically eliminated the entire black box and it's contents, the black vacuum line box on the left strut tower, the valve there also, the black air boxes (on the intake and in front of the upper timing cover), the aluminum valve for the black air boxes, and finally got around to cutting and capping the two metal tubes from the exhaust manifold. Hopefully tomorrow it won't be raining for the first time in weeks so I can get some pics! :)
 

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i want to see that done to a si fuel injection to see what it looks like at the end
 

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hey all. so, I'd love to do the weber conversion but can't just yet. instead I want to pull all the spaghetti vacuum lines. it looks like some of you guys have, how do I know what I can get rid of ? can you post a few pics of the set-up ?

1 year for antique tags !
 

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hey all. so, I'd love to do the weber conversion but can't just yet. instead I want to pull all the spaghetti vacuum lines. it looks like some of you guys have, how do I know what I can get rid of ? can you post a few pics of the set-up ?

1 year for antique tags !

The first few posts tell you which things can be removed (most of it actually), but I can see how it would be confusing unless you are fairly familiar with the engine. A picture of the end result might be helpful.

And hey, you're in the Chicago area. I'm up near Six Flags. :wave:
I'm curious, why would you want antique plates? We're already exempt from emissions now.

C|
 
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