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Doing a +t conversion on an unopened RB25DE NEO (R34 GT) Just before I list everything that I have done so far (not finished yet), I'd like to say that I've only been doing my own work on cars for the past 3 months and am not very technically knowledgeable on the field. I have however been given a vast amount of advice from real tuners and mechanics who actually do the conversions. If i have done something incorrectly please tell me so that I can change it. These are the parts that I had to use: Parts (R33 GTS-T IMPUL used as a donor car): R33/R34 turbo manifold gaskets ($55) R33 RB25DET turbo manifold R33 RB25DET elbow compressor R33 RB25DET S1 turbo with R33 RB25DET dump pipe 30CM extension to make the dump pipe meet with the cat which can be substituted by having a long decat pipe created by any exhaust place if you want a louder system(Instead of this, I just used the entire exhaust system from my 33 IMPUL sedan) R34 GTT injectors on an R34 rail R34 RB25DE NEO intake manifold (Re-used manifold gasket) 255LP Walbro fuel pump (Why not use this chance to start fresh and upgrade a cheap part) Fuel filter replaced R33 RB25DET S1 AFM (had to re-wire this which is easily done as you just have to merge two ground wires) R34 GTT AUTO ECU (You CANNOT use a NON-R34 ECU on an R34 as the LOOM has a different ECU plug. Some people on the internet will just tell you to use an R33 ECU like they did tome which is completely wrong so be careful. Also if you have an AUTO you wont be able to piggy back off of the N/A ECU so you will have to purchase an AUTO TURBO ecu and hopefully put a nistune on it. The person who sold me the nistune pulled some ignition timing off to compensate for the high comp engine in order to safely get the car to a tuner or be drivable. If you do use a manual ECU your auto system will be f**ked. If you use a standalone ECU your auto system will be f**ked. All of this information was given to me by the person who programs the nistune units and a few tuners have also advised me of these issues) Currently I do not have a BOV being used. The R34 N/A intake manifold is much longer then the turbo ones which does not allow me to use an R33 cross-over pipe. I do have theR34 and R33 turbo manifolds in my garage but want to see if the y-intake will work without a BOV. If there are issues, I will install an aftermarket BOV somewhere along the piping. R33 RB25DET S1 Inter cooler (I am using all of the stock inter cooler piping for now except for fabricating another piece of pipe in order to compensate for the short cross-over pipe) R33 RB25DET S1 O2 sensor (I had to also re-wire this as it was attached to the dump pipe before installed. If you can take it off and put the R34 one on that would be the best option but this was not possible for me as I had already put everything back together and I don't want to break my hands taking it off) OIL FEED: What I did for this line was tee into the stock oil sensor right next to the standard oil filter location. A brass "T" piece placed between OIL sensor (right next to oil filter) which runs a braided hose line via the T piece to the top of the turbo. OIL RETURN: The NEO block does not have the standard return plug so around 30CM to the left of where the standard oil return plug should be, there is a hole blocked by a plug (similar to sump plug). What I have done is run a high pressure and heat resistant 300PSI hose from a replacement bolt which attaches to the hose and is clamped down, the stock metal piece (also clamped). I did have to use an angle grinder to shorten the piece which fits under the turbo in order to avoid too many bent lines. WATER FEED + RETURN: Both of these lines were used in conjunction with the heater hoses which are near the firewall above the O2 sensor (The hoses are a decent size and will most likely be covered by a silver heat protector). I put a plastic heat resistant "T" piece in between where I cut both hoses and am running two corner pieces which bolt on to the sides of the turbo. My shitty tips: Be ready to improvise Every conversion has been different and don't be afraid to get creative If you are doing the conversion and expect to be done in a few days please don't do it. Expect the worst (unless you are knowledgeable on engines and/or have done this before) I went into the conversion assuming my car to be not drivable for a few weeks so I put it in the garage with decent lighting Take your bonnet and front bar off as soon as you start Try and keep the car in a garage with good lighting as this helps SO MUCH YOU DON'T UNDERSTAND I WAS USING MY PHONE'S FLASHLIGHT FOR THE FIRST FEW DAYS f**k THAT SHIT Be prepared to get around 50 cuts per hand and literally shed blood, sweat and tears (if it doesn't start) Keep track of every bolt, nut, screw, hose, nipple, ground (EXTREMELY IMPORTANT) and have the work shop manual printed if you can which is extremely helpful The intake and turbo manifold bolts are recommended to be torqued to spec (which I did but they still felt quite loose to me so I decided to tighten them further. You shouldn't get snapping studs unless you tighten/loosen at an angle due to R34s being a bit younger but be prepared for this to happen as it is common and fixable) The reason for the conversion is to get some hands-on experience with an engine. I did have an RB25DET I could have engine swapped but where's the fun in that. Also the higher comp engines apparently hit boost extremely early on in the RPM range which I wanted to experience for myself The whole process would be 150X easier with the engine out of the car (not that hard of a process) For the turbo lines, take your hard lines and possibly the turbo to a specialized auto shop. For example, I took mine to Adelaide's OG speed shop and they were able to sort out some lines for me. They were not right the first time around (due to a misunderstanding on my end) so I did have to improvise with the water lines as straight bolts do not fit on the sides of the turbo and corner bolt on pieces are much easier. It's hard to explain the whole turbo line setup so the auto shops will be able to help. In my opinion the turbo lines are the only "hard" part of the conversion and getting the right configuration for these lines was definitely the hardest step for me.