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This may be a dumb question but let's say that I buy a Skyline GT-R, probably an R32 in either the RB20DET or the RB25DET. I really want to get a feel for the car N/A before getting the power boost of a turbo. Can you take the turbo off of the engine and run it N/A? If so are there any modifications that need to be done beforehand? Thank you in advance for the answers.

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First off, R32/R33/R34 GTR's only come with RB26 engines as standard. Secondly these cars are so hilariously slow in standard form that "taking the turbo off" is a big waste of time. Must be school holidays again.

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That's a bit harsh, but I agree an unmodified skyline isn't really scary fast, no matter what you are coming from. You can control how much power it is making by just changing gears at lower revs (say, below 4000) until you feel comfortable.

And funnily enough, there are lots of threads on here about removing turbos from factory turbo cars due to various state P plater rules, the quick answer is it is neither cheap nor easy because the tune of the engine is substantially different

Oh I should add, if you just want to drive around the turbo car with no boost, you can remove one vacuum line to the blow off valve and all the boost will bleed off. But it will drive worse than non turbo car because the turbo cars came with lower compression in the first place

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Quote

This may be a dumb question but let's say that I buy a Skyline GT-R, probably an R32 in either the RB20DET or the RB25DET. I really want to get a feel for the car N/A before getting the power boost of a turbo. Can you take the turbo off of the engine and run it N/A? If so are there any modifications that need to be done beforehand? Thank you in advance for the answers.

You could pop the internal wastegates off; allowing the wastegate flaps to always stay open... you would not build any boost. Would be much easier to just take it easy on the gas pedal though.... And yes that is indeed a strange question and thing to want to do. 

Cheers. 

Edited by TurboTapin
3 minutes ago, Duncan said:

Oh I should add, if you just want to drive around the turbo car with no boost, you can remove one vacuum line to the blow off valve and all the boost will bleed off. But it will drive worse than non turbo car because the turbo cars came with lower compression in the first place

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3 hours ago, TurboTapin said:

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The BOV needs a pressure/vac source post-TB so it doesn’t crack open under boost but does open when the turbo is in boost but the intake runners are in vacuum. If you disconnect the vacuum line  for the BOV and cap the fitting on the intake it creates a substantial boost leak. Whether it’s enough to avoid leaking boost at all is hard to say.

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24 minutes ago, joshuaho96 said:

The BOV needs a pressure/vac source post-TB so it doesn’t crack open under boost but does open when the turbo is in boost but the intake runners are in vacuum. If you disconnect the vacuum line  for the BOV and cap the fitting on the intake it creates a substantial boost leak. Whether it’s enough to avoid leaking boost at all is hard to say.

Go pull your hose, drive around and let me know if "all the boost will bleed off."

Cheers. 

6 hours ago, redm0th said:

This may be a dumb question but let's say that I buy a Skyline GT-R, probably an R32 in either the RB20DET or the RB25DET. I really want to get a feel for the car N/A before getting the power boost of a turbo. Can you take the turbo off of the engine and run it N/A? If so are there any modifications that need to be done beforehand? Thank you in advance for the answers.

Yes, the modifications beforehand should be to take the turbo off, grind the compressor blades off using a Dremel, then re-install the turbo.

4 hours ago, TurboTapin said:

Go pull your hose, drive around and let me know if "all the boost will bleed off."

Cheers. 

I'm not suggesting it, it could cause issues with compressor surge because the BOV doesn't see vacuum when the throttle snaps shut, and I don't know what differential pressure is required to cause the BOV to open up significantly.

Personally I would just run wastegate pressure if "boost" is a big deal. A low compression N/A engine is nasty to drive.

it will bleed boost if the line is connected. how much? dont know.

should you do it? no

will OP get a GTR with an RB20DET and decide it needs less power? no.

 

 

 

and............... Overlooked by Duncan, understandably as the whole premise of taking boost away but leaving the turbo installed is a dumb idea that wont happen, car will run like shit as air bled off has been measured by AFM then escaped before engine. But who cares.

 

Umm, so on a standard gtr at least, removing the BOV vacuum line does prevent it making boost, a BOV wouldn't be much use if it couldn't bleed off all the boost a turbo makes. Also in the standard system it recirculates after the AFMs so it all works fine. This is how they used to limit boost in production car racing (pop off valve in the line between the manifold and the BOV which is triggered over a certain level, removes boost signal from BOV, BOV opens, fun over but car keeps driving fine just without any whoosh until the BOV reference sees pressure again).

on the other hand, I am not certain that disconnecting a wastegate actuator will prevent any boost being built either, it depends if sufficient gas can make it through the much smaller wastegate to prevent the turbine spinning.

clearly extensive testing is needed to determine best solution to OP's question.

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Don't you all know that it's possible to adjust how much you use the throttle? You don't have to push it all the way to the floor ;)

(speaking of that, I'm certain that most local cars are sold without one, as they have issues reaching 70 km/h in less than 2 minutes!) 

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22 hours ago, Super Drager said:

First off, R32/R33/R34 GTR's only come with RB26 engines as standard. Secondly these cars are so hilariously slow in standard form that "taking the turbo off" is a big waste of time. Must be school holidays again.

Okay, fair enough. What about if I wanted to get a GTS-T with an RB20DET but just take off the turbo? I'm not asking how fast it will be as speed is only important for sprinters and muh street racing. I don't do sprint, I prefer circuit or drift. How about answering the questions instead of judging the reasoning behind said question? mUsT bE sChOoL hOlIdAyS aGaIn

21 hours ago, Duncan said:

That's a bit harsh, but I agree an unmodified skyline isn't really scary fast, no matter what you are coming from. You can control how much power it is making by just changing gears at lower revs (say, below 4000) until you feel comfortable.

And funnily enough, there are lots of threads on here about removing turbos from factory turbo cars due to various state P plater rules, the quick answer is it is neither cheap nor easy because the tune of the engine is substantially different

Thank you for the advice.

15 hours ago, mlr said:

Yes, it is a stupid question 

Just recharge your Opal card instead

Unhelpful and somehow more dumb than my initial question.

15 hours ago, niZmO_Man said:

Buy R31 Skyline, plenty of power for a beginner driver.

I was thinking about maybe getting a GTS type S or M so I could get a feel of a Skyline in general and slowly upgrade over time. It is easier to find an unmolested GTS or GTS-T than it is a GT-R for obvious reasons. I prefer to stick with an R32 if possible. The one I was looking at at the moment was an HCR32.

12 hours ago, Ben C34 said:

it will bleed boost if the line is connected. how much? dont know.

should you do it? no

will OP get a GTR with an RB20DET and decide it needs less power? no.

 

 

 

and............... Overlooked by Duncan, understandably as the whole premise of taking boost away but leaving the turbo installed is a dumb idea that wont happen, car will run like shit as air bled off has been measured by AFM then escaped before engine. But who cares.

 

Thank you for giving some actual advice to the problems that can arise from doing this. Can you shed some more light on it or link some reading on the topic?

11 hours ago, mlr said:

Needs more NOS

fAsT aNd tHe FuRiOuS le may may

8 hours ago, Ben C34 said:

Thread made me retarded

Pretty sure that was your mom and her alcoholism in utero.

4 hours ago, K_arlstrom said:

Don't you all know that it's possible to adjust how much you use the throttle? You don't have to push it all the way to the floor ;)

(speaking of that, I'm certain that most local cars are sold without one, as they have issues reaching 70 km/h in less than 2 minutes!) 

So there is a reason I worded my post in the way that I did. I am wanting to know this because I am planning on getting a Skyline as a daily driver. Yes it is possible, because the Skyline is just a car. A car with a particularly sturdy engine. I believe most people have so many problems with Skylines because they want to molest the shit out of them and are to asinine to just drive a naturally aspirated or even in the case of a GT-R, just driving it as stock as possible minus upgrading for manufacturer defects in engine design such as the oil pan problem.

Extra boost is extra pressure, extra heat, and more wear and tear on not only the transmission but the internals. We're talking about a 25-30 year old vehicle. Also I love how everyone in this thread apparently is le master racer yet they can't understand getting to know the feel of a vehicle and how it handles naturally aspirated, how it handles weight distribution, turning radius, how it takes corners, etc. Why would I want to learn all this with a shit ton of power initially? That is just adding extra wear and tear on the internals when I know I won't be going balls out on it for a while. For instance, before I would even THINK about putting a lot of stress on an pre-95 RB engine I would be upgrading the spark/coilpack/ignition system (probably the platinum racing R35 conversion kit) given the arc problems the packs tend to come with leading to terrible misfires at high RPMs. Something that gets exacerbated with a f**king turbo being added.

While I don't know a lot about Skyline in particular as they have been illegal to have in the States doesn't mean I don't know cars in general. Some car manufacturers, Japanese and German specifically, are very finicky when it comes to removing stock turbos or super chargers. They aren't just bolt in, bolt out. So that is why I posted this. Jesus f**king Christ the amount of whining in a thread that you didn't even have to post in.

To those of you who kind of tried to give a decent answer, thank you. To those of you who decided to stick your finger in your ass and smear your phone screen with it as a response: You're cancer and no matter how high your post count no one is ever going to actually like you.

in b4 trolls bandwagon and pile on because they know I'm right

 

If you would like to post some helpful reading material and links please feel free to do so so I can get some actual advice.

 

 

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Edited by redm0th
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