RB25DE+T NEO (R34)

[hey_aleks]

RB25DE+T NEO (R34)

Hey lads,

I'm currently in the process of turbo converting my R34 non-turbo sedan. I have an R33 GTS-T Impul that I'm using as a donor car. Here is the parts I am using for the conversion:

• R34 GTT Intake manifold (I was given the entire intake manifold with GTT injectors and plan to install the whole thing instead of just the injectors and it Is a bit different to my DE one so I'm not sure if this will cause issues)
• R33 RB25DET turbo manifold
• R33 RB25DET turbo and dump pipe
• Walbro 255LP pump
• IMPUL 33 auto ecu (just to take it for a drive after finished, will be using my stock 34 ecu with nisstune after my tune on the 13th of SEPT

Now for my issue. Everything has been going good so far with no really complex issues except for the turbo lines. My NEO block has every water line plugged up with a metal plate and the oil feed is blocked off from the inside. I will be using the VTC plug which has a bolt in it for the oil return so that part is fine. I will also be putting a brass/metal TEE in between the oil sensor and the block and running a stainless steel braided line to the turbo from there for the oil feed. I have also been advised that I don't need water cooling as many people with stock turbos don't run them (a skyline mechanic told me this but i'm a bit cautious). So I was wondering how to exactly "tee" into the heater core for a water feed and water return as I've seen it suggested but have no idea how to do it. Any input to what I've done so far or my future plans would be greatly appreciated.

 

[DatsunBanana]

Hi, I'm currently gathering parts to +t my 34 too and planning exactly the same as you for oil feed and drain. I did think about running it with no water and lots of people say it's fine but I got a turbo timer to help prevent the turbo getting too hot after shutdown. I would still like to do water if I can though and tee-ing into heater pipework is an option but I haven't seen any specific details on this either. The science behind it seems to be that the return should be to a higher part of the system than the feed comes from. That way the hot water will naturally rise after the engine shuts off and pull colder water through the turbo. You probably knew/read that elsewhere already. I've got a couple of threads up at the moment with some questions about my other ideas for this - one is about getting the feed from the block water drain that exists on our NEO DE's right next to the blanked off turbo feed. The other is to return coolant to the front end of the inlet manifold as I think this could be done neatly by extending a standard water return pipe. I just don't know what the water channels are like inside there but you might be able to tell if you've got an inlet manifold already off the engine. Hopefully you'll get some definite answers and that might help me too.

[666DAN]

Run the water in parallel with the air-con heater hoses at the firewall (the ones that pass through the core on the internal)

[hey_aleks]

Just an update, I went to OG speed shop (in Adelaide) and the older lady there is absolutely brilliant. Literally sat me down for 3 hours and worked out exact what lines, bolts and T pieces I needed for the setup. Here's the exact setup for anyone with an RB25DE NEO wanting to turbo:

-OIL FEED: Brass tee piece placed in between oil sensor and block just next to the oil filter which runs to the top of the turbo through a braided line (AN8 SIZE LINE)

-OIL RETURN: There's a bung (similar to the one when draining the oil from under the car) located to the left of the DET place. I'll be using an extended 300PSI high heat rubber hose which is extended to reach that location.

-WATER FEED/RETURN: The heater hoses are literally to the right of where the turbo would be sitting so I'll be splitting these hoses and placing a brass T piece in between to run  two braided lines to the turbo.

I'm not 100% on the thread sizes and braided hose sizes so when I have all of the lines and bolts made (tonight) I'll post a pic and the exact length and thread size needed.

[hey_aleks]

Water feed/return:

• Both of these lines are identical for my setup (Using STOCK R34 GT NON TURBO INTAKE MANIFOLD)
• I've bought a meter of stainless steel braided hose for the setup (probably don't need that much but just in case something happens).
• The thread size going into the turbo is 18MM for these lines. This can either just be a straight piece or a corner piece which attaches to the braided line attachment.
• I am using a plastic (high pressure and heat) T piece to tee into the heater hoses aswell.
• So the T piece needs to be thick on the ends that we need to put through the heater hose and then the end that comes out needs to be able to fit inside of the braided line, but obviously be a bit tight. After draining your coolant, take off one of your heater hoses and go to a plumbing store with it and ask for a T piece which fits on both ends but also has an end for a hose (which will probably be around AN6 in size or AN8
• (yellow = heater core hose, grey = braided line, red = piece that attaches to braided line, blue = adapter to fit a thread, black tip = thread going into turbo, black T = T piece).