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Opinions Regarding Garett 2860 -5S On An Rb26


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I've got a dilemma at the moment which is that i've got a 300awkw GTR which i'm starting to get bored of the power.

300awkw just isn't that fast in a GTR, i'm running HKS GT-SS turbos at the moment.

So, i'm tossing up between going two large singles (2860 -5s or t518z's) or a big single like a t40z.

I've never been in a 400kw GTR, is it a lot more fun than a 300kw GTR?

Or do i need to go for a big single and aim for 450kw - 500kw?

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I was thinking that, but more boost means more strain on the motor right?

It's also a matter of not knowing what power level will make me happy.

A few others i've spoken to say that they've been in 400kw GTRs that felt amazingly fast, but my car feels so controlled and smooth in power delivery that it just doesn't excite me as much anymore.

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I was thinking that, but more boost means more strain on the motor right?

Boost is but one thing to consider right. You do know it's not the single factor in motor longevity?

If you can't afford. or don't want, the rebuild - anymore than 300rwkw is not for you. If you do have 15k standing by to go all out, then by all means chase the power.

You can get well into the "teens" at Sandown with those baby turbos and a well setup GT-R, and really, that is fking fast all things considered. So if you aren't there yet then you've got more to attend to than turbos for now :)

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well into the teens at sandown on GT-SS?? really?? i thought the well sorted, well driven, RP -5's R's were doing 18's, 19's?

just put in on E85 - i've got 2530's... but had i done the build myself i think i would have gone GT-SS equiv on E85 - i think for the street, that's the sweet spot unless you're a track junkie.

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faaaark me, 17 with -7's.... admittedly Chris was behind the wheel, a few seconds there! haha but still.... faark...

funny... i thought his car was -5's.... he's changed since yeah?

ok... maybe for 'normal' people who don't own/run GTR specific workshops, has anyone else got into the teens at Sandown with -7's? i thought everyone after, Jack, Ant, Snowy etc were -5's with semis?

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Ant isn't running -5s either far as i know. Newton driving Chris's car was into the teens a couple years back for a Dutton or similar and i think he did as well... This was before he took the reigns too :thumbsup:

End of the day my point simply is going fast @ the circuit is more about setup than it is about outright power, especially whilst learning. A lot more to be sorted out first. If you aren't going as fast as people around you with similar power then you've gotta improve setup and/or driving.

Given Harry has been doing c/ship rounds I'm guessing that is where he is heading in terms of direction. If it's just street he is talking about then do whatever fits my earlier post RE: budget/builds and so on.

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Ant isn't running -5s either far as i know. Newton driving Chris's car was into the teens a couple years back for a Dutton or similar and i think he did as well... This was before he took the reigns too :thumbsup:

End of the day my point simply is going fast @ the circuit is more about setup than it is about outright power, especially whilst learning. A lot more to be sorted out first. If you aren't going as fast as people around you with similar power then you've gotta improve setup and/or driving.

Given Harry has been doing c/ship rounds I'm guessing that is where he is heading in terms of direction. If it's just street he is talking about then do whatever fits my earlier post RE: budget/builds and so on.

Yep that's right i've started doing circuit work and love it, everytime i get out on the track i learn something new and have dropped time off my PB. I understand there are still significant time improvements to be had with current setup, but what i really wanted to get a better idea of was at what power level are most GTR drivers content? Is it just a case of you always get used to the power? I've heard lots of people running -5s with around 350kw saying that the power delivery just 'feels' much faster than the -9s. What about you Ash, are you happy with your current -5 setup at the moment? Do you know what i mean about the -5s feeling faster when they come on boost?

Boost is but one thing to consider right. You do know it's not the single factor in motor longevity?

If you can't afford. or don't want, the rebuild - anymore than 300rwkw is not for you. If you do have 15k standing by to go all out, then by all means chase the power.

You can get well into the "teens" at Sandown with those baby turbos and a well setup GT-R, and really, that is fking fast all things considered. So if you aren't there yet then you've got more to attend to than turbos for now :)

Yep, absolutley understand this, and I do have budget for a rebuild when/if it happens, again i was just more curious regarding at what power level other GTR drivers were content, since i've become used to 300awkw pretty quickly.

well into the teens at sandown on GT-SS?? really?? i thought the well sorted, well driven, RP -5's R's were doing 18's, 19's?

just put in on E85 - i've got 2530's... but had i done the build myself i think i would have gone GT-SS equiv on E85 - i think for the street, that's the sweet spot unless you're a track junkie.

Interesting you say this Daniel, i've seen one of our fellow sau members make 380kw on his gtr with hks gtss + e85. Possibly something to consider as an alternative to -5s to get up to my desired power level of around 370awkw.

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well into the teens at sandown on GT-SS?? really?? i thought the well sorted, well driven, RP -5's R's were doing 18's, 19's?

just put in on E85 - i've got 2530's... but had i done the build myself i think i would have gone GT-SS equiv on E85 - i think for the street, that's the sweet spot unless you're a track junkie.

Hi Daniel how do you find the 2530 on the street? I was thinking of getting these turbos for the power but have no idea how it feels in terms of lag and on/off boost response. Do you feel for the street that they are too lagy? I still have the n1 in my car and am now contemplating the gtss for the extra power without compromising response

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Yep that's right i've started doing circuit work and love it, everytime i get out on the track i learn something new and have dropped time off my PB. I understand there are still significant time improvements to be had with current setup, but what i really wanted to get a better idea of was at what power level are most GTR drivers content? Is it just a case of you always get used to the power? I've heard lots of people running -5s with around 350kw saying that the power delivery just 'feels' much faster than the -9s. What about you Ash, are you happy with your current -5 setup at the moment? Do you know what i mean about the -5s feeling faster when they come on boost?

They will 'feel' faster (esp on a 2.6) because of the transition onto power is so much more sudden. 5's (IMHO) really need a 2.8 + OR a high comp (9.2:1 +) 2.6 to work.

Interesting you say this Daniel, i've seen one of our fellow sau members make 380kw on his gtr with hks gtss + e85. Possibly something to consider as an alternative to -5s to get up to my desired power level of around 370awkw.

The jury is still out on that result. 1/4 trap speeds don't add up.

On the street the smaller turbo's will be faster and depending on what you're into more fun too. Coming out of a second gear corner and waiting for the snails to 'wakeup' SUCKS! You're halfway up the hill and it's "here we go!!!"... then you have to brake..... But it will look better on a dyno, so your pub talk will be a winner!

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Sorry to go off topic Harry but I think if you mainly do street driving you will get sick of any big turbo setup with extra lag that what you have now. On my gtt I have a big lagy turbo and it shits me, and also the constant gear changing to be in the sweet spot. But I no what you mean with the gtr and 300kw. These cars just handle the power so nicely and that you know it can take more without turning it into a pig

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Yep that's right i've started doing circuit work and love it, everytime i get out on the track i learn something new and have dropped time off my PB. I understand there are still significant time improvements to be had with current setup, but what i really wanted to get a better idea of was at what power level are most GTR drivers content? Is it just a case of you always get used to the power? I've heard lots of people running -5s with around 350kw saying that the power delivery just 'feels' much faster than the -9s. What about you Ash, are you happy with your current -5 setup at the moment? Do you know what i mean about the -5s feeling faster when they come on boost?

You always get used to the power.

I had the smaller turbos on there, for a street car that i took to hill climbs/motorkhana's and so on on the weekends it was the best setup.

Putting -5s on they are laggier, and 1st/2nd is pointless as you really need to be 140km/h++ before the -5s come into their own. The only reason -5s feel faster is because they take longer to spool and then hit harder with the torque later on. Yeah they make more power so at a track like Philip Island they might well give you benefit - but go to Sandown/Winton the smaller ones definitely shine.

Plus you'd still need to do transfer case, front/rear diff, suspension. They make the biggest difference dollar vs gains IMO over power/rebuild - just there is 10k on its own. So add in another 15k for the motor and everything and you've done 25k there. Hence why my GTR was such a bargin really @ 30k, and sold easily :)

Interesting you say this Daniel, i've seen one of our fellow sau members make 380kw on his gtr with hks gtss + e85. Possibly something to consider as an alternative to -5s to get up to my desired power level of around 370awkw.

And his MPH @ the track showed he didn't have anymore than 300rwkw at the time. So take the result with a massive grain of salt.

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I think you are after the kick in the back of the head that only a big single can deliver

transitional power from smaller twins is definitely not as exciting... but more useable in everyday conditions....

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I think you are after the kick in the back of the head that only a big single can deliver

transitional power from smaller twins is definitely not as exciting... but more useable in everyday conditions....

Or put GT RS's or 2540's on there. That will give that feeling !

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The jury is still out on that result. 1/4 trap speeds don't add up.

And his MPH @ the track showed he didn't have anymore than 300rwkw at the time. So take the result with a massive grain of salt.

yep... going to have to look into this after my holiday

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