Crank pulley question… and manifold


  • Crank pulley question… and manifold

    So… I am about to begin building a VG33ET for my '85 2+2. I am a professional mechanic, so I am well versed on how to actually perform the work, but I have been unable to find the answers to a few questions before I get started. The overview is I have a VG33E from a late '90s Pathfinder, and I plan on using my stock VG30E to supply the crankshaft, camshafts, and accessories. I will be using a new VG30E oil pump, as well as all the VG30E pulleys (see below) and accessories (alternator, water pump, etc.). Now to the questions…

    1. Did Nissan use the same crank pulley between the Turbo and NA versions from 1987+? I have done some research, and according to courtesyparts.com, Nissan only had one part number (12303-21V10) available for any 300ZX, whether Turbo or not, after 04/87. If this is the case, that means I can run this crank pulley in lieu of having a true '84 - '86 Turbo crank pulley? Obviously I would use an '87+ alternator, as I believe the only difference between the crank pulleys to begin with is the water pump and alternator belt. I also checked with 300zxparts4you.com, and he seems to have the same consensus, but I want clarification before I buy one. The main reason I ask is because locating a factory Turbo crank pulley seems to be ridiculous, and I have no availability on a true VG30ET to scavenge parts off of.

    2. Turbo manifold. I know the '84 Turbo came with an air-cooled T3, the '85 - '86 Turbo came with a water-cooled T3, and the '87+ Turbo came with a water-cooled T25. Forgive me, but I am a novice when it comes to turbo flanges. I plan on running a T25 turbo on my VG33, so does this mean I specifically need a turbo manifold from an '87+ model?
    1985 300ZX Z31 2+2 VG33ET (running!)

  • #2
    re, 2) The T25 used a T3 flange, the manifold is the same across all years. Personally, depending on how you're going to drive the car the T25 on a VG33 is going to be a little underwhelming (ask me how I know this.) Lots of get up and go for spirited daily driving but if you're looking to build a Fast Car it just doesn't push enough air.

  • #3
    Thanks for the response, and thanks for confirming that. I know a T25 is a little underpowered for a V6, but I am also not looking for absurd performance gains. I want a car that is fun to drive on the weekends, to take out on a cruise and have a little more "pep" than the other guy, and yet is completely reliable.
    1985 300ZX Z31 2+2 VG33ET (running!)

  • #4
    At 200-225hp at the crank you will surly be slower than the other guy…lol
    shotyme

  • #5
    Now, now… I didn't say anything about running stock boost . Push come to shove, I do have a T28 laying about somewhere…
    1985 300ZX Z31 2+2 VG33ET (running!)

  • #6
    T28 is still small for a 3.3 v6 you will have good bottom end but it will fall flat up top.

  • #7
    The turbo manifolds are the same, but VG30 runs m8x1.25 exhaust stud bolts vs the VG33 M10x1.25 studs. T3 is the minimum you should go with. Sounds like you plan to run an A/B series crank, in that case you need the early 87 pulley which is short snout all serpentine belt. Late 87 and up is W series long shout crank.
    Cha iro

    enjoy building it yourself.
    if it fails, fuck it.
    at least you gave it a whirl.

  • #8
    Thanks again for everyone's responses. News on my end, though… I'm acquiring an '85 Turbo parts car on Sunday . VG30ET is still there, though it is missing the turbo and the engine hasn't run in 20 years. I'm not too concerned about that, but it has all the other parts I need. I will probably be parting out what I don't need, so keep tuned for that if anyone is looking for anything specific.

    I already knew about the exhaust stud differences, I am going to elongate the holes slightly on the manifold to fit the VG33. Also, since everyone seems to suggest going bigger than T25s and T28s, what would be a good size turbo for my application? HX35 or HY35 off a Cummins, perhaps?
    Last edited by albionwanderer86; 07-25-2017, 07:39 PM.
    1985 300ZX Z31 2+2 VG33ET (running!)