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So ive taken off my stock rb20 turbo from my 32 gtst. Ive transfered the actuator from the rb20 to the rb25(higher psi - 10) but ive got a question....Whats this "nipple piercing" thing ive reading about. Im completely lost ATM. By the way, im using this guide:

http://www.project32.net/tutorials.php

as quoted from that webpage:

Nipple You may have noticed, the rb20 turbo has the nipple for the wastegate line direct to the compressor housing. Turbo reaches XX psi, wastegate opens, gasses pass into exhaust.

The rb25 doesn't, and relies on you t'ing the wastegate up to the outlet, preferably as close as possible to the turbo outlet itself. Depending on your piping setup, you may have a nipple in your piping simply blocked off � easy, don't have to do anything. If not, you'll have to tap into your piping a standard nipple.

You'll need to drill the piping, and then get the nipple (these can be purchased from supercheap or repco for a few bucks), welded in there, or if you can thread your piping, you can screw it in tight. Just make sure there is no leak, and that it can't pop off under boost.

Here you can see the nipple I have screwed into my existing piping. Done.

he also gives a pic:

turbonipple.jpg

If someone can explain to me, in a more general sense, what EXACTLY i have to do? what does welding a "nipple" onto the intercooler piping do? This "nipple"...what kind of bolt is it?

ill be forever grateful for your help :down:

Edited by IM-32-FK
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The nipple allows you to hook a pip from the nipple into your wastegate, allowing it to open the gate once the pressure is enough to open it.

Without running this line to your wastegate, the turbo will essentially free boost, and destroy itself (and possibly your motor) in no time.

I suggest you go into supercheap, explain you want a brass nipple vacuum fitting to screw into your intercooler piping. You shouldnt have too much trouble being pointed in the right direction.

Ive got a boost tap where one pipe runs to the actuator and the other runs into the actual turbo when i had my stock rb20 turbo in there....would i still need to put the nipple onto the piping?

diagrams would be helpful.

best thing is to buy a brass fitting to suit vac hose that has thread on one end.. drill a hole cooler pipe closest to the outlet of the turbo and wind the fitting on with a spanner and get someone to silversolder/weld it so its sealed. you can get brass fittings from most auto shops (veals)

Edited by BANGN
I just unscrewed the nipple from the 32 turbo and drilled and tapped the compressor housing on the 33 turbo to suit. The 33 housing still has the stand-off for the nipple only it's not drilled...

are you talking about this?

http://img235.imageshack.us/img235/9563/dyaln025.jpg

thats the rb20 turbo. The rb25 turbo has that same part but the hole has no threads or anything. Can i just take that part off the rb20 turbo and put it on the rb25 turbo?(if yes, do i drill it and tap it?) After ive done that, do i get another nipple any put it on the end of the hose and then weld it onto my intercooler pipe just before it connects with the crossover J pipe? or do i put the other end on the crossover pipe?

Edited by IM-32-FK
I just unscrewed the nipple from the 32 turbo and drilled and tapped the compressor housing on the 33 turbo to suit. The 33 housing still has the stand-off for the nipple only it's not drilled...

Thats exactly what I did too... just make sure you get as much of the swarf (metal shavings) out as you can.

On your pic you can actually see the blank where you can drill the hole out, tap it, and then put in the fitting that was on the rb20 turbo. All the hoses should go back onto the same places that they came off on the rb20 turbo, so forget about drilling/welding/tapping into your crossover pipe.

theres 1 nipple/port on the actuator. all you have to do is make sure that nipple sees boost when the motor sees boost. if you dont want to tap a fitting just buy a little T piece and T into one of the vac lines off the intake manifold, preferably not the fuel reg line.

Thats exactly what I did too... just make sure you get as much of the swarf (metal shavings) out as you can.

On your pic you can actually see the blank where you can drill the hole out, tap it, and then put in the fitting that was on the rb20 turbo. All the hoses should go back onto the same places that they came off on the rb20 turbo, so forget about drilling/welding/tapping into your crossover pipe.

thats not what the guy at skylines spares told me. I was told to just connect the actuator hose to the intercooler piping with a nipple on both ends...

Without running this line to your wastegate, the turbo will essentially free boost, and destroy itself (and possibly your motor) in no time.

off topic and just out of curiosity, which do ya think would happen first in the situation?

blown motor or turbo?

i got money on turbo, if were talking about stock ceramic ones.

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