Z31 NA2T build.... help locating where this vac line goes

  • bonfire79
    bonfire79
    Senior Member
    • 223

    Z31 NA2T build.... help locating where this vac line goes

    greetings,

    been a long time since I was on here last. so, I'm doing a turbo conversion on my 87 and I can't for the life of me figure out where the small vacuum line (on the black S-pipe) goes. where does this guy connect to? scratching head....

    Bon
    Attached Files
    • z31_vacline2.jpg (180.1 KB)
  • BLITZERKING1
    BLITZERKING1
    Member
    • 74

    #2
    Last edited by BLITZERKING1; 01-26-2017, 04:03 PM.
  • BLITZERKING1
    BLITZERKING1
    Member
    • 74

    #3
    On my 84 turbo I got rid of the s pipe (for intercooler piping) so I deleted the vacuum lines in front of the plenum. Also the one coming off the s pipe as well as the hose going to the valve cover (breather filter there now). Do you plan on using an intercooler or are you trying to keep it pretty stock?
  • Z_Karma
    Z_Karma
    Administrator
    • 3318

    #4
    Originally posted by BLITZERKING1 View Post
    http://www.thumper300zx.com/z31/vacuum/vacuum.htm

    According to this it looks like it goes to the AIV solenoid
    It actually goes to the charcoal canister. It's the green line that runs across the front upper cross member/support.
    It will typically have a inline diaphragm/check valve thing near where the upper radiator hose passes through.

    It's the green hose in this photo:
    diagram.jpg

    Props to Thumper for keeping his site up for so long.


    84 AE/Shiro #683/Shiro #820/84 Turbo
  • BLITZERKING1
    BLITZERKING1
    Member
    • 74

    #5
    Originally posted by Z_Karma View Post

    It actually goes to the charcoal canister. It's the green line that runs across the front upper cross member/support.
    It will typically have a inline diaphragm/check valve thing near where the upper radiator hose passes through.

    It's the green hose in this photo:
    diagram.jpg

    Props to Thumper for keeping his site up for so long.
    You're right. Ignore my previous post
  • bonfire79
    bonfire79
    Senior Member
    • 223

    #6
    Blitz / karma,

    thanks guys for your replies. you know what, it all makes sense to me now… I even printed out that vacuum line diagram from Thumper in order to replace the lines and I didn't even notice it saying that particular hose going from the pipe to the canister. what a knuckle head I am! since my engine is the 87 N/A, it already has its own lines running to the charcoal thing, so I think I can just delete and block the hose going from the S-pipe. EGR and AIV stuff already removed. all the turbo stuff came off of a JDM 200ZG that had the VG20ET.

    Blitz, for now I am planning on using the stock setup as my car is an NA2T. can't run much boost other than stock. if detonation gets bad, then I will add an intercooler at a later time.... trouble is finding one that will fit in that crammed up engine bay! smaller engine mounts and the deletion of the stock clutch fan may add to some room. still a pain in the arse though, hehe. considering a small oil cooler to help with keeping oil temps low. I'm leary of ebay coolers and a new Nissan one is ridiculously priced.

    will post some pics as the NA2T progresses. thanks again!

    Bonny
  • BLITZERKING1
    BLITZERKING1
    Member
    • 74

    #7
    Originally posted by bonfire79 View Post
    Blitz / karma,

    thanks guys for your replies. you know what, it all makes sense to me now… I even printed out that vacuum line diagram from Thumper in order to replace the lines and I didn't even notice it saying that particular hose going from the pipe to the canister. what a knuckle head I am! since my engine is the 87 N/A, it already has its own lines running to the charcoal thing, so I think I can just delete and block the hose going from the S-pipe. EGR and AIV stuff already removed. all the turbo stuff came off of a JDM 200ZG that had the VG20ET.

    Blitz, for now I am planning on using the stock setup as my car is an NA2T. can't run much boost other than stock. if detonation gets bad, then I will add an intercooler at a later time.... trouble is finding one that will fit in that crammed up engine bay! smaller engine mounts and the deletion of the stock clutch fan may add to some room. still a pain in the arse though, hehe. considering a small oil cooler to help with keeping oil temps low. I'm leary of ebay coolers and a new Nissan one is ridiculously priced.

    will post some pics as the NA2T progresses. thanks again!

    Bonny
    Yeah it is pretty cramped in there lol. To fit my front mount in I had to get an electric fan (taurus fan) and delete the stock clutch fan. My piping runs over the radiator and its really tight with 2.5" piping and a thick champion 3 core radiator. As long as you keep the boost at stock you should be good though. I ran my car at 8-9psi on 93 octane fuel (stock is about 6-7psi) before I had my intercooler and it ran fine. I don't know much about the JDM VG20et's though
  • bonfire79
    bonfire79
    Senior Member
    • 223

    #8
    Blitz,

    is your car an original turbo car or conversion? I have thought about doing over piping for intercooling, but I want to keep my a/c and it is a must over here in the middle east during the summer time! I just got a new turbo radiator (stock type) and the maxima fans allow room for more piping. the fuel rating over here starts at 91 and goes up to 98 or some crazy number. I just hope I don't get any knocks or pings!
    the JDM VG20 is just like its bigger 3 liter brother in looks, pretty much identical. it is just a bit smaller in size, and a 2 liter. everything I pulled off of it fit right on my VG30E perfectly except the exhaust crossover pipe, which was a bit shorter. the turbo is not a T3, but a TB250. looks the same to me though.

    I have to ask, did your 84 come with the stock aux fan that sits up in front of the a/c condenser?

    can't wait to kick the tires and light the fires!
    Last edited by bonfire79; 01-27-2017, 12:46 AM. Reason: correction
  • BLITZERKING1
    BLITZERKING1
    Member
    • 74

    #9
    Originally posted by bonfire79 View Post
    Blitz,

    is your car an original turbo car or conversion? I have thought about doing over piping for intercooling, but I want to keep my a/c and it is a must over here in the middle east during the summer time! I just got a new turbo radiator (stock type) and the maxima fans allow room for more piping. the fuel rating over here starts at 91 and goes up to 98 or some crazy number. I just hope I don't get any knocks or pings!
    the JDM VG20 is just like its bigger 3 liter brother in looks, pretty much identical. it is just a bit smaller in size, and a 2 liter. everything I pulled off of it fit right on my VG30E perfectly except the exhaust crossover pipe, which was a bit shorter. the turbo is not a T3, but a TB250. looks the same to me though.

    I have to ask, did your 84 come with the stock aux fan that sits up in front of the a/c condenser?

    can't wait to kick the tires and light the fires!
    It's an original 84 turbo GLL model with digital dash. Yes it came with an aux fan (it cools the injectors I believe) but I took it off. I expect to get new injectors and nistune soon anyway. You can keep your ac but the intercooler piping can be tricky. If you want to make keeping the ac and routing piping easy I'd recommend a 85-88 nissan maxima front entry upper intake plenum
    https://z31performance.com/forum/z31…maxima-intakes
    Last edited by BLITZERKING1; 01-27-2017, 01:06 AM.
  • bonfire79
    bonfire79
    Senior Member
    • 223

    #10
    Originally posted by BLITZERKING1 View Post

    It's an original 84 turbo GLL model with digital dash. Yes it came with an aux fan (it cools the injectors I believe) but I took it off.
    https://z31performance.com/forum/z31…maxima-intakes
    hehe, I was actually referring to the electric type fan that sits in front of the car (not the injector one) the turbo supposedly came with one that was attached to the front of the condenser. looks kind of like the maxima fans, but it is only one.

    I have read about the tricky dick stuff that can be when routing for an intercooler.... funny how it is so easy and common on the cars pre Z31, but such a pain on the 300zx. be nice to locate one of those old Spearco kits. I have thought about the maxima plenum or even the pathfinder one, but I've already spent so much money on this car and engine already… don't want any more mods and headaches
    I do like how those plenums have the TB up front instead of on the side like our Z. I think I will try and go through the fender, you know cut a hole and run a pipe. I've read of a few guys doing that to make routing easier. I also heard, doing away with the old stock motor mounts and using the smaller poly-urethane ones can make room for putting piping down there from the turbo. and I also recently saw something on xenonzcar that can help… a pre-welded circular bracket motor mount that allows a pipe to pass straight through and fit in the stock position to support the engine. I think it is still in the testing phase, but might another option to try.

    thanks for all your good input.

    Bon

  • BLITZERKING1
    BLITZERKING1
    Member
    • 74

    #11
    Originally posted by bonfire79 View Post

    hehe, I was actually referring to the electric type fan that sits in front of the car (not the injector one) the turbo supposedly came with one that was attached to the front of the condenser. looks kind of like the maxima fans, but it is only one.

    I have read about the tricky dick stuff that can be when routing for an intercooler.... funny how it is so easy and common on the cars pre Z31, but such a pain on the 300zx. be nice to locate one of those old Spearco kits. I have thought about the maxima plenum or even the pathfinder one, but I've already spent so much money on this car and engine already… don't want any more mods and headaches
    I do like how those plenums have the TB up front instead of on the side like our Z. I think I will try and go through the fender, you know cut a hole and run a pipe. I've read of a few guys doing that to make routing easier. I also heard, doing away with the old stock motor mounts and using the smaller poly-urethane ones can make room for putting piping down there from the turbo. and I also recently saw something on xenonzcar that can help… a pre-welded circular bracket motor mount that allows a pipe to pass straight through and fit in the stock position to support the engine. I think it is still in the testing phase, but might another option to try.

    thanks for all your good input.

    Bon
    Yes my car had a fan on the AC condenser. I deleted all the AC stuff from the firewall forward though. Also I just used heavy duty 3" exhaust pipe and drilled a hole for a bolt in it as my motor mount. You can also use a tight 90 turn or just run a filter on your turbo and go with a blow through maf setup
  • kaur
    kaur
    Senior Member
    • 310

    #12
    Octane ratings are different in some countries. 93 in the US should be similar to 98 in Europe, for example.
    https://en.wikipedia.org/wiki/Octane…rement_methods
  • bonfire79
    bonfire79
    Senior Member
    • 223

    #13
    Originally posted by kaur View Post
    Octane ratings are different in some countries. 93 in the US should be similar to 98 in Europe, for example.
    https://en.wikipedia.org/wiki/Octane…rement_methods
    yup, the same here in UAE. 98 is close to the 93 back home in the US. most local stations start out at "E-Plus" at 91, special at 95, and super at 98. and they have some special gases for odd-type vehicles and trucks.

    Bon