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Discussion Starter · #1 ·
Hi guys,

I read all threads about turbo upgrade of garrett and still have one question missing.

Due to the garret site the difference between 7s and 9s is:
> 707160-7
> Products | Turbochargers
> Compressor Ind Whl Dia(mm) 44.60
> Compressor Exd Whl Dia(mm) 60.10
> Compressor A/R 0.42
> Turbine Whl Dia(mm) 53.90
> Turbine A/R 0.64
>
> 707160-9
> Products | Turbochargers
> Compressor Ind Whl Dia(mm) 44.50
> Compressor Exd Whl Dia(mm) 59.40
> Compressor A/R 0.42
> Turbine Whl Dia(mm) 53.90
> Turbine A/R 0.64

So everything is almost same.

The site says that powershift is same Horsepower : 150- 310
Even 9s has smaller Compressor Ind and Exd Wheel diameter.

Could anyone advise why 9s can make more power with same responce as 7s can, as member Austrian GTR says.

Thank you in advance.
 

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Look at the compressor maps mate, there you'll find the answer :)

The dimensions might be about the same, but that doesn't mean the compressor or turbine wheel is ;)

The horsepower stated on their website is based on the rule of thumb that 10lb/min is about 100hp...

...but it's also about efficiency (cooler air means more power).

Cheers,

Leo
 

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You've missed the Trim value.
Generally speaking a higher trim wheel will flow more than a smaller trim wheel.

-9s = 56 Trim
-7s = 55 Trim

The trim of a wheel, whether compressor or turbine, affects performance by shifting the airflow capacity. All other factors held constant, a higher trim wheel will flow more than a smaller trim wheel. However, it is important to note that very often all other factors are not held constant. So just because a wheel is a larger trim does not necessarily mean that it will flow more.
 

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I have ben reading lot of threads/pages about these two turbos and as well the "-5" and I'm still in doubt if go with the -9 which happen to have the same response as the -7 but with more top end where is a WIN-WIN situation for the -9 vs the -7 in most cases.

However I'm in debate if go with -5 or -9 for my needs and HP gal which is no more than 550 HP crank and street/track (I would say the car would be used 50% street time and 50% track). I know the -5 is laggier but the boost won¿t drop off at higher RPM or about 8k rpm where the -9 should drop some boost and that makes me think I will regret from the -9 if I go that route.

Hard decision...

Turbo PN 707160-5 47.20 60.10 62 0.60 53.90 76 0.64
 

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It is a tough one, -5 will give you top end for sure, -9 are equiv to GTSS according to a few sites. But remember the rest of your engine must be pretty good to get the same sort of power Leo got, which if the rollers were not too ambitious is pretty amazing!!

-5 should give you 650 bhp flywheel at least should you wish for a bit more power later. Remember cams and adjustable pulley will mean you can tweak when boost comes on strong.
 

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-9's have the same response of -7's up to 1bar...however-7's are slightly faster than -9's in reaching higher pressures (for example from 1bar to 1.5bar of boost)...but -9's have a bettere top end (for example -7's work good up to 7500rpm while -9's up to 8000rpm). Ultimately these two types of turbochargers are good for working up to 8000rpm in general; if you want to work beyond the threshold of 8000rpm then you should buy a pair of 5-'s. This applies if you're talking about 2.6L. If you are using a displacement of 2.8L then you should definitely consider -5's. This is my opinion..
 

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-9's have the same response of -7's up to 1bar...however-7's are slightly faster than -9's in reaching higher pressures (for example from 1bar to 1.5bar of boost)...but -9's have a bettere top end (for example -7's work good up to 7500rpm while -9's up to 8000rpm). Ultimately these two types of turbochargers are good for working up to 8000rpm in general; if you want to work beyond the threshold of 8000rpm then you should buy a pair of 5-'s. This applies if you're talking about 2.6L. If you are using a displacement of 2.8L then you should definitely consider -5's. This is my opinion..
Great advise! :bowdown1: What max bost pressure do you think can handle the -9 in a stock RB26 with top 8K RPM limit? I would say in other way, could handle up to 550 crank HP with good supporting "bolt on" mods in a stock RB26 the -9 turbos?
 

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Great advise! :bowdown1: What max bost pressure do you think can handle the -9 in a stock RB26 with top 8K RPM limit? I would say in other way, could handle up to 550 crank HP with good supporting "bolt on" mods in a stock RB26 the -9 turbos?
At this time I am helping my friend to prepare his RB26 with stock internals. He owns a r34 which has already turbines hks gt-ss (precisely the-9's), Nismo 600cc injectors, Nismo fuel pump, Nismo fpr, APEXI power fc l-Jetro with std afm, etc... the current output is around 430hp at the crank at 1.3bar of boost (mapped conservative). The next goal is to bring the power of 550-600hp at 1.4/1.45bar boost: so I decided to advise my friend to mount the tomei poncam type A camshafts (I took example from the experience of Leo with his r32), and in addition the Nismo AFMs. I would advise the same preparation because I think it is the best compromise between power and response. To learn more about the performance of the gt2859r -9, you should look at garrett compressor map on the website; in this way you will notice that this turbocharger maintains its maximum efficiency up to about 1.6bar.
;)
 

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At this time I am helping my friend to prepare his RB26 with stock internals. He owns a r34 which has already turbines hks gt-ss (precisely the-9's), Nismo 600cc injectors, Nismo fuel pump, Nismo fpr, APEXI power fc l-Jetro with std afm, etc... the current output is around 430hp at the crank at 1.3bar of boost (mapped conservative). The next goal is to bring the power of 550-600hp at 1.4/1.45bar boost: so I decided to advise my friend to mount the tomei poncam type A camshafts (I took example from the experience of Leo with his r32), and in addition the Nismo AFMs. I would advise the same preparation because I think it is the best compromise between power and response. To learn more about the performance of the gt2859r -9, you should look at garrett compressor map on the website; in this way you will notice that this turbocharger maintains its maximum efficiency up to about 1.6bar.
;)

Thanks for the information. I wonder how much time are you going to be able to re tune the car and see what is the max power you can achieve with the -9's turbos and the current setup?
I also was thinking to throw some Tomei Poncam B at some point because I was thinking to go with -5 turbos and I read few threads that either, A or B cams were worth the mone for the HP goal in mind (550 crank HP or even better 600 crank HP).

So you think by adding Poncam A and add 0.15 more bars at the engine with good tune you would be able to get that HP goal with the -9's turbos?
 

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Thanks for the information. I wonder how much time are you going to be able to re tune the car and see what is the max power you can achieve with the -9's turbos and the current setup?
I also was thinking to throw some Tomei Poncam B at some point because I was thinking to go with -5 turbos and I read few threads that either, A or B cams were worth the mone for the HP goal in mind (550 crank HP or even better 600 crank HP).

So you think by adding Poncam A and add 0.15 more bars at the engine with good tune you would be able to get that HP goal with the -9's turbos?
Ecu tuning is not only adding more boost...there are many points to touch...i don't known about the future dyno result, but you know about Leobnr32 dyno result with 1.35bar: 600bhp
More ignition advance and more boost give you more hp! If 1.4/1.45 will not be sufficient we will add more boost..(100 octane fuel)
 

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Ecu tuning is not only adding more boost...there are many points to touch...i don't known about the future dyno result, but you know about Leobnr32 dyno result with 1.35bar: 600bhp
More ignition advance and more boost give you more hp! If 1.4/1.45 will not be sufficient we will add more boost..(100 octane fuel)
I forgot: we must give more boost pressure because , unlike the preparation of Leo , my friend keeps the stock intercooler , and the stock suction kit. He also decided to keep the L- Jetro with nismo air flow meters , while Leo is passed to the map sensor ( maybe a few hp more ) ..
But these are just guesses . However, we are confident that we are in a minimum range of 550 - 600hp .
I can tell you with certainty that if you're going to place the rev limiter at 8000rpm , you 'd do well to buy the gt2859r to work in that area. But in addition to turbokit , you need to put the right camshaft. In my opinion the poncam type A is right for this configuration ( they are cheap ;) ) . Basically you should buy a type of camshaft with a duration between 250 ° and a maximum of 264 ° , because it is useless to put a camshaft with an excessive duration , and I think you know why. I advise you not to go beyond 10mm for the lift ( for example mine 's camshaft is 252 ° - 10.05mm in / ex ... there are many alternatives )
 

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Mines do not go crazy on exhaust duration, their stage 2 setup is 252 with 9.5 lift and 260and 10.2 on the inlet. The Tomei Type A is similar, but lacks the lift on the inlet.

You can go procam to be close and go for the 260 10.25 lift and 252 9.15 on exhaust or Kelford do a 256 and 9.5 for the exhaust cam.

I think for this setup -5 would be a better option as they will be more efficient at top end compared to -9
 

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Discussion Starter · #14 ·
Guys so I have Tomei poncam B 260 9,15 in and exh
N1 crank, forged pistons in 87 diameter

As I understand its better to have 5s?

Still between 9s and 5s...:confused:
 

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Mabe you should finally state where you want to go ;)

As you might have already read on here, there's more involved in tuning than just putting together some parts and there's always a cheaper and a more expensive route to achieve a certain amount of hp, it just depends on how drivable you want the setup to be...

...for example, a well built and tuned setup with -9 turbos and 600bhp will be a lot quicker and better to drive than a pretty stock setup with -5's where you need lesser mods to achieve the power...

...in other words if you're just after big power figures, throw in the bigger turbos and you'll easily achieve your goal...

...if you want a setup that works also well in lower and mid revs then you'll need a smaller turbo and also work out the rest...

...peak hp is just a number at a certain point of the rev range...

...my goal is and has always been to get the biggest area under the power curve, because this is what you can actually use whilst driving :thumbsup:

Cheers,

Leo
 

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...peak hp is just a number at a certain point of the rev range...

...my goal is and has always been to get the biggest area under the power curve, because this is what you can actually use whilst driving :thumbsup:

Cheers,

Leo
Well said Leo, I believe quite a few people don't understand this concept.
 

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Discussion Starter · #17 ·
Mabe you should finally state where you want to go ;)

As you might have already read on here, there's more involved in tuning than just putting together some parts and there's always a cheaper and a more expensive route to achieve a certain amount of hp, it just depends on how drivable you want the setup to be...

...for example, a well built and tuned setup with -9 turbos and 600bhp will be a lot quicker and better to drive than a pretty stock setup with -5's where you need lesser mods to achieve the power...

...in other words if you're just after big power figures, throw in the bigger turbos and you'll easily achieve your goal...

...if you want a setup that works also well in lower and mid revs then you'll need a smaller turbo and also work out the rest...

...peak hp is just a number at a certain point of the rev range...

...my goal is and has always been to get the biggest area under the power curve, because this is what you can actually use whilst driving :thumbsup:

Cheers,

Leo
Leo

I'm same looking for driveability and like engine working not for small range of big power but low and mid range of torque.

I wrote the main specs of my engine - what you can say if 9s will work fine on it or advise what I need to add to acheive good balance between response and hp?

May be your mods you made?
 

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The problem is majority of skyline owners seem to care about big numbers and want the biggest single turbo they can afford and bang it on. There is this drag mentality that has poisoned the minds of people for too long. It's good to see more recently some are looking at ways of creating a good track and all round performing car.

I am building my engine at the moment I will get the internals as strong as possible for my power target of around 600-650 with the emphasis on response and the way the power is delivered. Turbo should be the last of your concerns you should start spec up your bottom end such as oil pump, baffle, crank, rods pistons etc.. Then top end such as valves springs caps titanium or std, cams, ported head?

You really need to work out a budget and do it properly.
 

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You really need to work out a budget and do it properly.
:thumbsup:

May be your mods you made?
If it's 550bhp you're after with the best driveability and you're not on a budget then I'd definitely go for -9's mate :)

Anyway, I never said the mods I did are the best or the ultimate...

...but for me they worked out well an better than expected.

But with tuning an engine it's the same as with many other things...

...ask 3 people and you'll get 3 different answers.

I gained a lot of experince on my old DC2 turbo and my engine builder and I did a lot of development work on that engine with great results...

...all I'm doing now is using this experince to setup an RB26 to my own preference, which does not actually mean someone else will like it too.

I'm currently working on my new engine setup whit lot of additional mods as I really want to get the most out of the -9's as possible (also because I'm curious to see what this tubs really can do :smokin:).

Engine tuning is so complex, so for the start it's always good to do your homework and go from there :thumbsup:

And again, putting together the right parts is just half of the story...

...the best engine setup is usless without a proper mapping ;)

Just on a side note, Group A GTR's had also between 550 and 600 bhp from smallish turbos and they spent a lot of time and money with engine development and finding the right setup...

...so also they must have had their reasons why to go this way even it would have been easier to throw in bigger tubs to get to the goal ;)

Guys so I have Tomei poncam B 260 9,15 in and exh
N1 crank, forged pistons in 87 diameter
There is no such thing as a N1 crank ;)

There's a early R32 (narrow oil pump drive), a late R32 + R33 and a R34 crank.

Cheers,

Leo
 

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:thumbsup:



If it's 550bhp you're after with the best driveability and you're not on a budget then I'd definitely go for -9's mate :)

Anyway, I never said the mods I did are the best or the ultimate...

...but for me they worked out well an better than expected.

But with tuning an engine it's the same as with many other things...

...ask 3 people and you'll get 3 different answers.

I gained a lot of experince on my old DC2 turbo and my engine builder and I did a lot of development work on that engine with great results...

...all I'm doing now is using this experince to setup an RB26 to my own preference, which does not actually mean someone else will like it too.

I'm currently working on my new engine setup whit lot of additional mods as I really want to get the most out of the -9's as possible (also because I'm curious to see what this tubs really can do :smokin:).

Engine tuning is so complex, so for the start it's always good to do your homework and go from there :thumbsup:

And again, putting together the right parts is just half of the story...

...the best engine setup is usless without a proper mapping ;)

Just on a side note, Group A GTR's had also between 550 and 600 bhp from smallish turbos and they spent a lot of time and money with engine development and finding the right setup...

...so also they must have had their reasons why to go this way even it would have been easier to throw in bigger tubs to get to the goal ;)



There is no such thing as a N1 crank ;)

There's a early R32 (narrow oil pump drive), a late R32 + R33 and a R34 crank.

Cheers,

Leo

Hi Leo,

well said:) Do you have a dyno chart from your last tune/setup? What's the peak TQ and HP you made so far witht he -9 and your mods? I'm pretty much set on these -9 turbos.

Thanks,
 
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