| Ok a few members asked me to do into detail over what modifications were needed to make the turbos off a Skyline R32 and R33 fit on the 90-96 300zx. Ok both the Z32 manifolds and the skyline turbos have the same 4 bolt flange, the only problem is that they both have 4 studs coming out of them. So you remove the rear two studs on the exhaust manifolds and the front two studs on the turbos and drill through holes. The manifolds will require some milling, since the EGR bung is located over the inside hole you just drilled out on the drivers side manifold, It will need to be cut back and milled flat so that a nut can sit on a flat surface. On the other side you need to mill two flat spots arond the thru holes so those nuts can sit flat too. The same needs to be done to the back of the exhaust housing to let those nuts sit flat too. Also since you cut down your EGR bung you probably wont be able to use it so you will have to have the hole welded shut. The other studs you didn't remove in the manifold and turbo will now have to be removed and replaced with ones about a 1/4in longer, since you need to put a spacer plate in between the manifolds and turbos. Just take some 1/4in thick steel and use one of the gaskets to use as a template and punch out the 4 holes and mill out the center. This is done so the larger compressor housing wont hit the engine block. You can either weld it to the turbo or just use a gasket on each side(what i did). Here is are some pics of a flange and the removed studs and through holes on one of the turbos, and one of the flange welded to the manifold 
Now that the turbos can actually be bolted to the engine you will need to clock them. Look at your stock turbos to get an idea of what direction then need to go and then have fun getting them to spin. Loosen the bolts and throughly coat the housing and side you are trying to clock in WD-40 or some other type of penetrating oil. I had mine in a vice and was hitting them with a piece of wood and a hammer trying to get the exhaust housing to break loose from the center section. Be Careful because instead of just spinning the center section will want to come apart and angle to the side, if it does this it could bend the shaft or break some blades off the turbine. I just losened the bolts so it wouldnet have the chance to come apart, just spin. Get it clocked correct so that your oil return line is lined up, then tightne the exhaust side down and get your intake side lined up (much easier to clock). Now that you got your turbos clocked and line up with the oil return line you will notice that since the compressor housing is bigger the oil return line hits it and wont reach the center section. You will need to put an extender plate on it so it will reach the center section. Luckily my skyline turbos came with one stock oil return line, so i just cut the flange off and welded it to my return pipe, it gave me the extra 3/8ths of an inch that i needed. I got another stock line from a junkyard and did the same thing, cutting that flange off and welding it on, you will now need longer bolts for your oil return line since there is a spacer. Ok so now you notice that the inlet flange to the compressor is not at the same angle. You will need to take the two inlet pipes and cut off the two bolt flange rotate it about 45deg and then Braze it back onto the pipe. (I tried TIG welding it but the metal is so thin that it was near impossible. I ended up torch welding/ brazing them with copper rod. Also the two bolt flange on the turbo and pipe look the same but the holes on the turbo are slightly closer together, so you need to slightly slot the holes on the pipe flange. Pic of an installed inlet pipe at the correct angle
Ok now you have to make a two bolt compressor outlet flange on your skyline turbos bolt up to the stock turbos 3 bolt alum elbows. I cut some alum pieces and welded them to each side of the elbow flange and then drilled holes so i could bolt it on. Ive also heard of people just welding the elbow to the turbo as you can see in the pic above. Here is a pic of the elbows with welded tabs from someone else's buildup
You can also see in that picture that the wastegate actuator bracket was cut off and re welded at the correct angle. Make sure you do this after your turbos are clocked because it will change things if you don't. Now the drivers side actuator was a cinch but the passenger side is a nightmare. I had to cut my motor mount and shave one of the bolt heads to get it to fit in there, since on this side its in between the motor and the turbo, and not on the outside like the drivers side. You will need to cut and weld the bracket and get the actuator as close into the turbo as possible so that there is more room for it to go up next to the block. Like i said i had to cut my motor mount to get it to fit, and even after i did that it was pressed up against the mount my turbo housing and the block. I tried to space it as far away from the manifold as possible to avoid heat damage. I also wrapped it in some heat reflective shielding as well as the actuator hose just to be safe. Now that the actuators are at the right angle the rods will most likely be too long. Mine were close enough that i put the rod in a vice and bent it in a slight zigzag patter to shorten the length ever so much. YOu can cut the rod and thread each end of the cut part and use the adjustable nut method, which involves a long nut that you screw a rod into each end to the correct length then use a jam nut on each end to keep it from spinning. It was such a tight fit i had to remove my motor mount and alternator bracket, then put the turbo on then replace the motor mount and then the alternator bracket to get things to fit. Here is a pic of someones nut shorting method 
Ok Down pipes, the exhaust flange on the stock turbos is a 4 bolt, and the skyline turbos is a 5 bolt. This 5 bolt pattern in not the same as the Sport 650s so those downpipes wont work either and neither do the stock Skyline downpipes because they come down at the wrong angle. First i made my own 5 bolt flanges to weld on to some custom downpipes i was going to make , but i ended up buying a set of Greg Dupree downpipes and since the flanges were almost large enough i then drilled holes in the correct places. This required welding an extension of the flange on the side to fit a 5th hole. Then i went to the hobby store and bought some 1/16in thick copper sheets and made my own gaskets. I wouldn't use high temp fiber, it gets too hot for that. Here is how the downpipes look bolted up 
Ok you are almost done you will need to connect all the oil and water lines from your stock turbos to the Skyline ones, this is a pain in the butt and some lines need to be connected to the turbo before you bolt the turbo to the manifold. Also if you put studs that were too long on they will interfere with the lines. Other than that put new copper washers in and you might want to sand your flanges flat on any of the pipes you welded, since the heat could have warped them. Hopefully you got your downpipes and inlet pipes at the right angle, after i put my engine in my passenger side intake pipe was touching the strut tower, so i stuck the end of a baseball bat in there and bent it away. Your stock TT exhaust might bolt up if you got your downpipes at the right angle but it will probably need to go to the muffler shop to get fitted. I think thats it, if i left anything out let me know My price breakdown Turbos from Devin Novak - $350
Downpipes from Greg Dupree - $370
Copper sheet - $12
Longer studs and various fasteners - $20
Hours and hours of fabrication time - Priceless I was able to get free scrap materials for the flange extensions, and i did the machine work and welding, except for the alum welding and torch brazing which friends did for me for free. If you don't do this fabrication work yourself it could cost upwards of 500$ to have a machine shop do the work. Feel free to move this to the Technical forum or Vote to FAQ if its any good. Oh by the way i have lots of extra parts, flanges, longer studs, copper gaskets and other stuff needed for the conversion plus a set of stock turbos with down pipes and testpipes ----------------------------------------------------
I GOT AN ENGINEERING INTERNSHIP! WOOHOO for me :) -Justin
91 TT stgIII++ black on black
~darkside~
R33 turbo conversion is done :)
 No ricing a domestic it is called GRITs or griting out LOL - RT ~IM Cheezoto~
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*Complete* Skyline Turbo Conversion List -rehosted pics- - 
