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Discussion Starter #1
Morning all,

I know standard turbos (with ceramic giblets) are "safe" to 1.0 bar...

What kind of boost can you realistically run with them sorted with steel bits inside? I'm presuming you're limited by the size/flow of the turbo rather than a might shatter type break scenario. So, what might I be able to run steel standards on? How does that compare to HKS 2530s ? What is their max boost?

Thanks

Jon
 

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Bolting on direct replacement steel blades onto the factory turbos won't get you a lot more room for boost. The factory turbos were "designed" to operate at about 1 kg/cm2 so pushing them beyond 1.2 kg/cm2 begins attracting decreasing returns to scale, both on the compressor (heat) and turbine (backpressure) sides.

On the other hand, the HKS 2530s were designed to operate in higher boost conditions and actually start their sweet spot from 1.2 kg/cm2. ith those turbos you could go up to 1.7kg/cm2 before starting to encounter the same decreasing returns to scale as mentioned earlier.

Note, these are simply indicative numbers - your mileage may vary.

Cya O!
 

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BHP difference

At Tuning Japanese,Guy`s R33 LM (now Durzels) made about 480bhp with steel internals,his R34 with 2530`s got to 570-580BHP both figures at the flywheel.

Keep the boost down,trust me.

Maybe Guy could follow this post up with more info.?

Henry.
 

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steels vs 2530s

Both were a while ago, so I can't remember the exact figures, though I recall the 2530s made 545bhp (I think), can't remember the steels.

Generally I'd say a set of steel internal stock turbos are not efficient above about 1.2bar and are limited to about the 460bhp level. A set of 2530s are efficient to about 1.5bar and good for about 570bhp.

The above will depend on other engine mods and tuning (cams/intercooler are necessary for power above).

There is little point running steel internals as if you want more power it is a better step to jump to bigger aftermarket turbos (for not much more overall cost).

There is no point running high boost unless you have big big turbos as the compressors are beyond efficiency and all you do is make heat, not power. and lower the longevity of your engine.

Guy
 

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What about lag??

At what point in the PRM range would you expect to hit full boost on these turbo's - Ceramic vs. Steel vs. 2530's

This will make a huge difference to the drivability of the car.
 

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Re: steels vs 2530s

off topic ....hi guys this is my first post here and my english isn't that good so i need help from you guys .. i'm planing to buy those bolt ons turbos such as HKS 2530 but the thing is i dunn know where to buy them from or how much do they cost in $ dollars shipped to the middle east ...... thanks in advance
 

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Alex h

Lag is not a factor.........change down a gear.

Henry.
 

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Re: steels vs 2530s

Guy said:
Both were a while ago, so I can't remember the exact figures, though I recall the 2530s made 545bhp (I think), can't remember the steels.

Generally I'd say a set of steel internal stock turbos are not efficient above about 1.2bar and are limited to about the 460bhp level. A set of 2530s are efficient to about 1.5bar and good for about 570bhp.

The above will depend on other engine mods and tuning (cams/intercooler are necessary for power above).

There is little point running steel internals as if you want more power it is a better step to jump to bigger aftermarket turbos (for not much more overall cost).

There is no point running high boost unless you have big big turbos as the compressors are beyond efficiency and all you do is make heat, not power. and lower the longevity of your engine.

...............................................................


what do you expact to run in the 1/4 mile if you are running 1.5bar or 550Hp GT-R ?
i read somewhere a gtr with 2530 + nos run high 10's @ 137 ...but that run was @ 1.7bar + nos ...
 

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NOS makes a huge performance difference, especially if it was a sizeable shot. The car that ran 10.7 is Motorex's R33. That car was being pushed very hard to get that time. On straight 2530s with a well tuned engine and driver you should be able to hit low to flat 11s (non-stripped GT-R) readily.

Cya O!
 

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So when DO the 2530s build boost compared to the std turbos, and how does the spool up time compare?

Sometimes it's nice not to have to change down ... (I'm lazy too).

And is the 2530 the 'next size up' from the stock turbos?
 

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Next Step up.

HKS GT 2510`s are the next step up,they are excellent turbos and depending on cams will pull hard from 3,000rpm.These are brilliant trackday turbo`s and I should know as I covered over 30,000miles on mine before I moved on to the GReddy T517Z`s.

Peter E. and Jamie M. are well known 2510 users and Shin and Dirk Diggler (Andy Barnes) are of course two of the many 2530 guys on this Forum.

The GT25 range will give you anything from 480BHP to 620BHP at the flywheel depending on how modified your RB26 is.The 600BHP figures are achieved from the GT2540 and "R" versions.

Aren`t Saturdays boring without a Skyline to play in.:(

Henry.
 

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2510s eh - Jamie M has (by the sound of it, having read a few of his posts) around 520bhp at the flywheel and a very good spread of torque. As I'm thinking about the 500bhp mark in a Skyline, the 2510s may be just what I need.

I presume that the 2530 allows you to produce a bit more power than does the 2510 but at the expense of slightly less grunt at the bottom end?
 

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You could always put on a set of N1 turbos and get your spool as fast as (if not faster than) the HKS GT 25 series turbos while making your 500-550hp target comfortably. Probably cost you less as well. Just a thought.

With regards to the power delivery of the HKS GT turbos (all other things equal or matched appropriately), the higher the number the more top end power at the expense of low down power. That is, 2530s will make more power at later rpms while 2510s will make more power earlier in the rev range.

Cya O!
 

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So are N1 turbos generally better all rounders than the HKS 25 series? Why do so many people use the HKS turbos if the N1s are so good?
 

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Dont quote me on this but I think that the HKS 25 series turbos are slightly better than the N-1 turbos. The N-1 turbos are stockers but with a metal internals. The housings are still the same. The compressor wheels may be a little larger but I dont think so. I would still take the 25 series over N-1 turbos.



Chris
 

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R-33VSpec karma said:
Dont quote me on this but I think that the HKS 25 series turbos are slightly better than the N-1 turbos. The N-1 turbos are stockers but with a metal internals. The housings are still the same. The compressor wheels may be a little larger but I dont think so. I would still take the 25 series over N-1 turbos.



Chris

how much are these N1 turbos plus where can i find them ?
 
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