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Can you remove a stock rb25 turbo without jacking up the car?


sonicz
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Just a point of order......compare the sizes of the turbines between the eBay cheapy and the highflow.  The relaive size gives you some idea about how much power each will support and therefore how much gas they need to also bypass through the wastegate.  The cheapy won't need the wastegate hole ported out anywhere near as big as that massive hole on the highflow.  But it definitely will need it ported.  You'll need to open it up by at least 2mm of diameter.  You still need to have enough overlap of the flapper onto the seat for it to provide a gas seal though, so don't go too crazy.

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1 minute ago, GTSBoy said:

Just a point of order......compare the sizes of the turbines between the eBay cheapy and the highflow.  The relaive size gives you some idea about how much power each will support and therefore how much gas they need to also bypass through the wastegate.  The cheapy won't need the wastegate hole ported out anywhere near as big as that massive hole on the highflow.  But it definitely will need it ported.  You'll need to open it up by at least 2mm of diameter.  You still need to have enough overlap of the flapper onto the seat for it to provide a gas seal though, so don't go too crazy.

You're 100% correct, but they're the only pics I had on hand (highflow vs ebay) so that's what I used.

I had the exact same turbo on my RB25 R32 and it creeped like a b!tch.

Anyway OP, as we've both suggested, you need to port the wastegate.

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Ok to get first things first. I just called plazman luckily beore going there, and they dont have anything of the sort for a turbo oil drain hose or a 90 degree 1.5 to 2 inch silicone hose for the piping. I was told to go to him as he would have it but luckily i called ahead and nada, they said they are an inter cooler manufacture place.

You would think i was looking for a rare part of a an alien mothership not a common place "tuner" care

 

Next place I go to is pirtek. Otehrwise I am out of ideas and will just use a radiator hose, or can anybody recommend a substitute oil drain hose that will do the trick? A clear silicone hose from bunnings by the metre and cut to size?

 

Moving on. Yes you are right, my turbo looks like first two pics. Now I let me get this straight, I'm guessing that I need to port the wastegate so that more boost pressure can be bypassed and I dont boost creep too much? Where do I get it done and wont the metal shaving f up the turbo? I have a boost controller, so if I set that to the lowest, what will my boost be? I think the stock AFM can handle up to 14psi without hitting its max value. With the lowest boost setting, are you guys telling me my boost will be greater than 12ish psi without the turbo ported?

Edited by sonicz
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eBay for both your hoses. Get the right stuff. 

Yes, we're saying you need to physically widen the hole. A boost controller won't do squat as it only controls when the flapper opens. The problem will be that even when fully open it won't bypass enough gas and your boost will creep. There is no workaround for this physical issue. 

You wont fk up the turbo if you do it right, which involves taking the exhaust housing off the turbo, carefully measuring the material you want to remove and then dremelling it out. 

A turbo workshop or metal fab place can help you out. 

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Do it yourself.  Die grinder.  Shove a rag into the volute.  Tape over the turbine outlet.

Oil resistant hose is available literally everywhere.  Pirtek will do.  But just about any mechanic's workshop will have rolls of it and will sell you a little bit.  As will truck parts outlets, any hydraulics outlet (like B.L. Shipways, etc).

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22 hours ago, Yeedogga said:

Hate to thread jack- but OP do you also realise you will need a tune (or at least some dyno time to check everything) after you get it running?

Definitely recommended for the health of the car, but I ran my old RB25 R32 with a replacement ebay turbo (almost identical to this) without issue for 2 years. So yeah, recommended yes, but "need", no.

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Lol. I just put a car on my dyno this weekend for someone with that attitude who said car was running fine,
16:1 AFR lower loads. Still in the 15's comming onto boost, didn't go past that yet he had been thrasing it like that.
Its all fine while the engines running until your halfway threw natio and it's suddenly not running.

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2 hours ago, Scott Black said:

Lol. I just put a car on my dyno this weekend for someone with that attitude who said car was running fine,
16:1 AFR lower loads. Still in the 15's comming onto boost, didn't go past that yet he had been thrasing it like that.
Its all fine while the engines running until your halfway threw natio and it's suddenly not running.

Surely it depends on the amount of boost though right?

Yeah, this turbo has more puff, but if he ran it at 10psi or less he ain't doing major damage?

Happy to stand corrected. Even if wrong I think this guy has bigger problems lol (he probably hasn't been backing after revealing the shit he's in, poor lad)

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6 minutes ago, inmaniac said:

Surely it depends on the amount of boost though right?

Yeah, this turbo has more puff, but if he ran it at 10psi or less he ain't doing major damage?

Happy to stand corrected. Even if wrong I think this guy has bigger problems lol (he probably hasn't been backing after revealing the shit he's in, poor lad)

Nope.  Fatal mistake.

Bigger turbo @ same boost WILL be flowing more air.  The turbo has a bigger compressor AND a bigger exhaust side.  The bigger exhaust housing seriously reduces backpressure on the engine, which increases flow at the same boost.  In the best case, you simply stay on the Nissan map, go up into the top right hand corner and have massive R&R.  In the worst case, your fuel pump is not up the demands, you might have one or more dirty injectors, your CAS might have jitter out the waazoo, and you won't know because you didn't put it on the dyno to reassure yourself that it's not about to carve up the ring lands, plate them onto the combustion chamber and send the residue out into the exhaust.

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6 hours ago, GTSBoy said:

Nope.  Fatal mistake.

Bigger turbo @ same boost WILL be flowing more air.  The turbo has a bigger compressor AND a bigger exhaust side.  The bigger exhaust housing seriously reduces backpressure on the engine, which increases flow at the same boost.  In the best case, you simply stay on the Nissan map, go up into the top right hand corner and have massive R&R.  In the worst case, your fuel pump is not up the demands, you might have one or more dirty injectors, your CAS might have jitter out the waazoo, and you won't know because you didn't put it on the dyno to reassure yourself that it's not about to carve up the ring lands, plate them onto the combustion chamber and send the residue out into the exhaust.

Welp, there you go. I always thought that you could still "play it safe" on a bigger turbo by keeping the boost low. I'll stand corrected by those more experienced :happy:

Glad I got so much time on mine with no tune and thrashing it - I guess I was lucky!

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Well for comparison take a gt3582 compared with a stock turbo, yes its noticeable bigger yet at 14psi your talking a power increase of about 50%. Yes its not as bad at lower pressure. Yet also consider the timing on a lot of stock Nissans isn't that conservative so as well as fueling differences can have pinging, especially at mild loads cruising (stock ecus have heaps of timing there) nice loud exhaust radio up on the highway cant hear anything wrong.
You might get away with it and things might be OK. Yet you might not and more often than not its not safe. And some dyno time is a lot cheaper than a rebuild.

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Thanks for the input so far guys.

Unfortunately this never ending saga seems to have no end in sight but I have no choice but to keep going. I had a look at some youtube videos on how to port the wastegate and its surprisingly not that scary of a task. In fact its probably the most simple, just gently slashing away at a hole making it bigger and this part of the process actually 100% understand how it all works.

However, As always A NEW CHALLENGER appears which to most people is plain and simple and I'm ready to get the sledge hammer out.

I did get new a silicone new hose of ebay, and after doing a tour of Sydney I did find a 1m length oil resistant hose at a turbo specialist store for the turbo oil drain.

The silicone size I needed turned out to be 51mm to 60mm 90 degree reducer if anyone is interested. The new turbo compressor outlet is 51mm so the small side of the silicone fits to this nicely, and the stock piping of the skyline is around 60mm so the fat part fits this nicely. I also got a cut away steel pipe from an exhaust shop about 4 inches long and just under 60mm diameter.

20171003_165957.jpg

Problem solved. right? WRONG

WTF I totally did not realize the Turbo air inlet is so much bigger on the new turbo than the stock one.

The new turbo is 3 inches and the stock one is what 2 inches? 

It goes from this

20171003_165711.jpg

To this

20171003_165729.jpg

In no way shape or form is this a "direct factory replacement!" The ebay listing  literally said that!

The hose that connects to the turbo air inlet is the rubber one with lots of hoses coming out of out. Its wasy to small to connect to the air inlet of  the new turbo. How DAFUQ do i get around this?

Seriously Aside from getting a full new hoses and piping rework of the entire RB25 engine incl manifolds and and 3 inch piping inter cooler kit I have no idea what to do. Is there any part that replaces this stock rubber hose on the left but has a 3 inch side?

Untitled.jpg

Frankly I'm surprised nobody mentioned running into this problem.

If I had idea idea it was going to be this much modification i would have just got another used stock turbo even if it cost me 350. I'm already over that in parts I never wanted.

Also how DAFUQ do you adjust boost on the new turbo? It has no nipple on the wastewater actuator like the stock turbo does. What do I do with the left over nipple? Is it just one boost waste gate settings and I turn the nut on the wastegate rod to extend the flap for less boost or closed for more?

20171003_171038.jpg

 

p.s lease let me have some sanity but not making me think about tune until its at least hooked up.

 

 

 

 

Edited by sonicz
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Um.....pretty much any non-stock turbo replacement ends up with a fabricated steel turbo inlet pipe.  You shouldn't even use the stock rubber inlet elbow on stock turbos because they suck closed under high load!  You're going to need something made.  If you were in Melbourne it would be trivial.  Just point you at Scotty.  Could still do that.  Just get him to send you one.

As to the wastegate.  No, the length of the rod just adjusts the pre-load, which doesn't affect max boost so much as prevents creep.  You can only adjust boost on an internal gat's actuator if that actuator has an obvious adjustment on it (a screw on the end of the can, like you'd expect to see on an external gate's actuator).  If you want to adjust boost you have to use a bleeder or an electronic boost controller (which is just a glorified bleeder, really).  You can't turn the boost down.  You can only turn it up (from whatever the actuator's spring will give you).

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Regarding the difference in pipe size, you can get a reducer piece. One that is 3" on one end and 2" on the other. 

I'm no expert. Just offering my 2 cents worth....

As mentioned the stock elbow collapses under load. Rather replace with alu piping or so

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1 hour ago, GTSBoy said:

Um.....pretty much any non-stock turbo replacement ends up with a fabricated steel turbo inlet pipe.  You shouldn't even use the stock rubber inlet elbow on stock turbos because they suck closed under high load!  You're going to need something made.  If you were in Melbourne it would be trivial.  Just point you at Scotty.  Could still do that.  Just get him to send you one.

As to the wastegate.  No, the length of the rod just adjusts the pre-load, which doesn't affect max boost so much as prevents creep.  You can only adjust boost on an internal gat's actuator if that actuator has an obvious adjustment on it (a screw on the end of the can, like you'd expect to see on an external gate's actuator).  If you want to adjust boost you have to use a bleeder or an electronic boost controller (which is just a glorified bleeder, really).  You can't turn the boost down.  You can only turn it up (from whatever the actuator's spring will give you).

yea I'm seriously only finding everything out as a I go long.  None of this was planned normally i research things but not at this time.. I'll look around on gumtree ebay see what I can find. Do you know what part exactly sucks closed? Maybe I can insert something to keep it open like a round metal ring?

 

Do you know how much scotty sells them for?

So something like this?

http://www.ebay.com.au/itm/Silicone-Induction-Intake-Hose-Pipe-Skyline-R32-Turbo-RB20DET-Blue/281486828881?rt=nc&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D20151029142714%26meid%3D9d5300b1bf41458bb71d0b944c8b1276%26pid%3D100005%26rk%3D1%26rkt%3D6%26sd%3D271912832930&_trksid=p2047675.c100005.m1851

RE. the wastegate, I'm still 100% confused whats going on... I already have adjustable boost controller on the car. It was working perfect with old turbo and could easily adjust boost between

say 6psi to 14 psi etc depending on how much i turned the allen key on the boost controller setting.  However as shown in the pics the old turbo had a nipple on the waste gate that something connected to, which i presume is how the boost  was controlled. The new Turbo does not have that. So how do I get the new turbo to have adjustable boost? The wastegate is just connected back into the housing of the turbo.

s-l1600.jpg

 

49 minutes ago, Die$eL said:

Regarding the difference in pipe size, you can get a reducer piece. One that is 3" on one end and 2" on the other. 

I'm no expert. Just offering my 2 cents worth....

As mentioned the stock elbow collapses under load. Rather replace with alu piping or so

Yea i really panicked on the spot as I I figured it would not be enough room but I guess its possible. Will have to look around whats available but I dont see how it will work unless the reducer goes from soft 3 inch silicone plastic or rubber suddenly to a metal 2 inch pipe to insert into the stock skyline reducer pipe.

 

EDIT. Guess I can use a pure silicone reducer with a pipe inside, but them there will be a naked pipe handing freely mid air mere cm from a spinning compressor blade..

I also realized if i get a reducer there would be no point in the turbo having a 3 inch inlet, might suffocate it, so better to get a proper 3 inch pipe for it right?

Edited by sonicz
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What's your goal with the ebay turbo? Do you just want a replacement for the stock one or do you want more power aswell? If the latter then you'll find you will end up spending a fair bit on supporting mods at which point you may as well ditch the ebay turbo and get a hypergear hiflow or something. If you were happy with the stock turbo then it would be easier just to wait for one in good condition to come up for sale, i think i have even seen a few on the forum lately for around $150. I sold my stock turbo in great condition with only a small amount of shaft play for $140 (i regret it).

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6 hours ago, sonicz said:

RE. the wastegate, I'm still 100% confused whats going on... I already have adjustable boost controller on the car. It was working perfect with old turbo and could easily adjust boost between

say 6psi to 14 psi etc depending on how much i turned the allen key on the boost controller setting.  However as shown in the pics the old turbo had a nipple on the waste gate that something connected to, which i presume is how the boost  was controlled. The new Turbo does not have that. So how do I get the new turbo to have adjustable boost? The wastegate is just connected back into the housing of the turbo.

The blue hose on the actuator is the on the nipple you are looking for - you just need to route it from the boost source (the turbo housing or the original source nipple, depending on what you do with the intake pipe) through your boost controller and back on to the actuator.

 

Re the ebay silicone intake pipe - I'm not convinced this won't also suck shut. I've got an alloy one that came from ebay, but I don't think they are available anymore. I'd contact Scotty's Customs - he makes a very nice metal replacement.

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11 hours ago, sonicz said:

Do you know how much scotty sells them for?

RE. the wastegate, I'm still 100% confused whats going on... I already have adjustable boost controller on the car. It was working perfect with old turbo and could easily adjust boost between

say 6psi to 14 psi etc depending on how much i turned the allen key on the boost controller setting.  However as shown in the pics the old turbo had a nipple on the waste gate that something connected to, which i presume is how the boost  was controlled. The new Turbo does not have that. So how do I get the new turbo to have adjustable boost? The wastegate is just connected back into the housing of the turbo.

s-l1600.jpg

 

Yea i really panicked on the spot as I I figured it would not be enough room but I guess its possible. Will have to look around whats available but I dont see how it will work unless the reducer goes from soft 3 inch silicone plastic or rubber suddenly to a metal 2 inch pipe to insert into the stock skyline reducer pipe.

 

EDIT. Guess I can use a pure silicone reducer with a pipe inside, but them there will be a naked pipe handing freely mid air mere cm from a spinning compressor blade..

I also realized if i get a reducer there would be no point in the turbo having a 3 inch inlet, might suffocate it, so better to get a proper 3 inch pipe for it right?

 

4 hours ago, GeeDog said:

 

The blue hose on the actuator is the on the nipple you are looking for - you just need to route it from the boost source (the turbo housing or the original source nipple, depending on what you do with the intake pipe) through your boost controller and back on to the actuator.

 

Re the ebay silicone intake pipe - I'm not convinced this won't also suck shut. I've got an alloy one that came from ebay, but I don't think they are available anymore. I'd contact Scotty's Customs - he makes a very nice metal replacement.

Per all the above.  The boost source for boost control is off the turbo outlet.  The place where boost control happens is at the actuator.  Hence the simplest way to make that happen is to connect one to the other.  The boost signal then pushes the actuator to open the wastegate.  But it offers no adjustability.  So the way to obtain that is to take the signal from the source, bleed some of it off and pass the reduced signal to the actuator.  Presto, now the actuator sees a lower boost than the engine sees and you can happily run higher boost than the actuator is sprung for.  But, and this is a very important but, you cannot decrease boost below what the wastegate actuator is sprung for.  If you have a 14 psi spring in there now, then 14 is the minimum.  Hence all my cautions about not tuning etc etc in earlier posts.

And to go back to the topic of the inlet elbow, you should never use soft silicone bends there.  Call Scotty, buy whatever he makes.  It doesn't matter what it costs, it is the only reasonable way for you to achieve your goal (of getting it all fitted together and running).

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