New to Z31 Perf.... Happy to be here and wanting to go n/a to turbo.


  • New to Z31 Perf.... Happy to be here and wanting to go n/a to turbo.



    Hello everyone. I am new at this forum, but I am usually over at zcar.com daily. I figured since this site is relevant and specific the Z31 and since I own a Z31, why not spend some time over here. Something new, something fresh. Anyways, I'm glad to be here.

    So, I've got an 87 n/a 2+2 5-speed in stock form that I love and drive daily, unless she breaks! Me mental dilemma is this…

    I want to turbo charge the car. Turbo Z's are hard to come by in my location. So, I have been toying around with the idea of doing a stock late Z31 turbo setup. I've gone over REDZ31's site more than a few times and done my research over on some other sites. Though There are a lot of options and complications, I do not see what cannot be done to make this a reality.

    Goal-wise, all I am looking for is just to give this Z a bit more kick. I love the 9 to 1 compression and the high torque that it gives me to get up quick around town. I suppose the R-200 3.90 in the back has a bit to do with that. I would like to see a little quicker throttle response once it really gets going down the road. I'm not looking for high boost or racing applications. In fact, I was thinking more along the lines of the stock setup of an 88 - 89 turbo and still be able to retain the air conditioning. Logically, it seems the safest, most efficient, and cheapest pay route to go. more like, the best bang for the buck.

    I figure that using the following parts would be sufficient and easy to come by and able to swap right in:

    - 88 - 89 T ECU & H.I injectors. Wiring harness???
    - T25 Turbo Charger assembly and associated piping, water, and oil lines.
    - exhaust manifold, elbow, downpipe, O2 sensor, and TPS.
    - intake piping, oil cooler assembly, T idle control valve, and replacement cross member or modification.

    after doing some reading, I don't think it is really necessary to use an intercooler with the small amount of boost that the T25 produces. And I don't think it would be too much harm to use in conjunction with the n/a pistons = higher compression. I mean wouldn't they compliment each other? 4 -5 psi of boost is not that much. What was the compression ratio in the 88 car, 8.3 to 1 or something similar?

    I have found after going over parts diagrams from courtesy parts Nissan, that the MAF, TB, distributor, fuel pump, FPR, flywheel, and several other parts are the same on both the n/a and turbo cars? So, I think there are many things that aren't needed to swap. I may be wrong on that.
    I am not sure if the turbo bypass valve and the knock sensor are really needed either.

    I think this could be a safe, fun, and reliable application. So, why not? My motor has to be torn down anyways because it eats up oil (worn parts… valve seals, valve guides, and piston rings, I suppose) At least this is what I think is happening in there… there is some kind of internal miss fire. maybe a sticky valve? Anyways, I am considering having the engine overhauled, so if am going to go turbo, now would probably be the time to do it.

    Your experiences? What do you think? Am I out of my mind?

    Thanks,

    Bon

    -from Abu Dhabi, United Arab Emirates.








  • #2
    You can use the 87T ecu/turbo/manifold/injectors with premium fuel and cautious timing, it will have the larger T3 turbo (although still small)

    There are other options for cheating the fuel like rising rate pressure regulators and such

    87's were quite common so finding the parts shouldn't be hard as long as you don't mind the shipping costs, you can also get nistune for the 87 ecu later if you want, and low-imp injectors are easier to find cheaply…

    You should state a budget though, you can do a mild turbo swap with custom manifolds and non-nissan turbos too, depending on labour and item costs, you might end up with a similar end cost

  • #3
    thank you, G-E for the info. a budget is what I need to do. after going thru all the parts lists for a stock late Z31 turbo setup, the cost is quite high, especially the parts coming from courtesy Nissan. like you say, it might almost be cheaper to go the nistune route with a mild turbo setup with custom manifolds and exhaust. there is a little shop here that I take my Z in for maintenance, and they pretty much specialize in turbo charging the newer vehicles… (every Nissan patrol over here seems to be turbo charged… the n/a V-8s aren't fast enough for the owners I guess…) anyways, I am going to go and talk to them about the nistune idea and see what we can put on the table. I did some digging around you tube, and what I like about nistune is that it still uses the stock box. so I could use the n/a box I already have with everything attached. you can even check codes without having to remove the thing and looking at the blinking lights. and as of now, the lights blink 5 times red and 5 times green which indicates all systems good

    there are more things I have to consider however… running an intercooler will be a tight fit. I've read that putting the poly-euro thane motor mounts in place of the stock rubber mounts can make a bit more room in that area. I need to look at injectors too. and also find out how much the nistune chip and installation will cost. wonder how long it take for them to install and ship? in the meantime, i'll see what the mechanics at the turbo garage can do. you're right, perhaps labor-wise it be easier and cheaper to do it this way.

    options options options

    thanks! i'll keep posting and seeking advice as things go along.

    Bon

  • #4
    ECUs are fairly cheap on ebay so I suggest getting a separate one if you want to nistune, that way you can drive the car on the stock ECU if Nistune's being tricky

    The only problem with a custom turbo/manifold setup is that there's nowhere else to put the turbo besides the stock location unless you lose the A/C. I am guessing that in Abu Dhabi you probably need to keep the A/C. Then you need to worry about the crossmember/motor mount and the oil pan.

    If you don't need the A/C, a lot of possibilities open up. I removed the A/C and relocated my turbo, but it never goes above 30 degrees here. All I needed to do was swap my alternator to the passenger side and punch an oil return into the pan, I didn't need to swap crossmembers.

    This is the first big decision you need to make - if you need the A/C you are more or less stuck with doing a 'stock' NA2T whether you use the stock parts or not.

    One thing you could consider is that if you need A/C but not power steering, you might be able to put the A/C in the P/S location; you would need to have new lines fabbed and extend some wiring but it might work. Then you could have a relocated turbo *and* A/C. I don't know if anyone's ever done that before. edit: This wouldn't be a cheap option but it still might be cheaper than buying all the used swap parts from the US or whatever and getting them shipped to you.

  • #5
    Originally posted by bonfire79 View Post
    there are more things I have to consider however… running an intercooler will be a tight fit. I've read that putting the poly-euro thane motor mounts in place of the stock rubber mounts can make a bit more room in that area. I need to look at injectors too. and also find out how much the nistune chip and installation will cost. wonder how long it take for them to install and ship? in the meantime, i'll see what the mechanics at the turbo garage can do. you're right, perhaps labor-wise it be easier and cheaper to do it this way.
    If you really need more space, I would redo the engine mount setup entirely, move them to the frame rails, and cut the humps off the cross member for example… don't feel limited by how the car was made, it's just a little cutting and welding

    Installing an intercooler can be done many many ways, side outlets, vertical outlets, a mix? You can also look at relocating things to make space

    Since I don't imagine you get much rain or drive in puddles, you can even move your airbox into one of the front fender caviities, likewise you can relocate your battery to the trunk… again be creative

  • #6
    There's plenty of room for the intercooler, it's the routing of the piping that can be a pain. If you don't need climate control, it's easy to route the piping after deleting the A/C compressor. Otherwise, the old HKS system ran piping underneath the rad cradle and created a low point that would bottom out on lowered cars, or the Spearco kit that goes over top of the radiator but has a LOT of bends to it, or the option of running the piping through the inner fender wall and through the driver's wheel well. A custom radiator mount and/or a front-entry intake plenum can make things a lot easier too. There are quite a few options based on budget and level of creativity, and ton of build threads to use for guidance if you don't mind doing a little searching and reading here.
    Zoey - 1987 Z31T GLL - HKS EVC / CM SS 3" turbo-back / Stance GR+
    Black Betty - 2014 Audi C7 S6 APR1