The Ultimate Turbo for your RB25DET

[Sydneykid]

From Grepins Thread, posted by SK   regarding the GT2835proS

Hi grepin, I like it, it has....

270 rwkw at 7,300 rpm

277 rwkw at 6,300 rpm

246 rwkw at 5,300 rpm

210 rwkw at 4,300 rpm

That's an average of 251 rwkw over the useable rpm allowing for gearchanges. There are plenty of cars with over 300 rwkw that don't average 251 rwkw.

I think it would be a nice car to drive, fast and progressive.

BTW guys, notice this dyno run was not in Shoot Out Mode, so no ambient air temperature compensation. If it was a 31 degree day, then on a 19 degree day it's gunna make a smidge over 300 rwkw with an average around 270 rwkw.

Wanna guess what the A/F ratios would be then? In my opinion Mick has done a good job, looks to be both safe and powerful, you don't see that everyday.  

As I said at the start, I like it!

Some more info came to light after that original post that may clarify a few things;

HKS 2835 ProS Internal gate, at 1.65 bar. A Greddy Plenum, after market exh manifold (Tillbrooks), and Sard 550cc inj, PFC computer and Q45 throttle body.

I dont run that boost all the time, however with 10% toluene 28 deg day the worst knock was 21

Personally I like to set up my car so that it has its max power whenever I push the throttle down. I don't want to wait to "turn up the boost" and "stick some toluene in it". I want to be able to go fast anytime I like and for as long as want.

With the GCG ball bearing high flow on the R34 GTT we could turn up the boost (it runs 1.3 bar all the time) and stick some TurboMax in it and make another 35 rwkw. That would bring it up to 300 rwkw, but not EVERYDAY, not ALL the TIME, not WHENEVER I want.

That's the big difference to me personally, other people may well be happy with spending an hour or 2 before they can go fast.

[DoughBoy]

That's assuming the GCG huge flow can support the additional boost.

[BU5TER]

would a jim berry clutch suit this turbo?

[SLY33]

in regards to grepin running 1.6bar boost and toluene, wasnt that just during early runs? i thought he had a boost leak and got it sorted, ending up with somewher round 280rwkw at 1.2bar with no toluene?

[DoughBoy]

As ylwgtr2 mentioned, maybe a Tackleberry clutch is in order for those high shooting motors?

[SLY33]

in regards to grepin running 1.6bar boost and toluene, wasnt that just during early runs? i thought he had a boost leak and got it sorted, ending up with somewher round 280rwkw at 1.2bar with no toluene?

trust33, im not sure why garret and hks equivalents arent the same, but im sure its been covered somewhere else.

[SLY33]

 

Also being that all of these turbos are rated at stock boost 10psi or so.So there will be room for more power.

i dont think they are rated at stock boost. i thought HKS's were rated at 1 bar, which may be true for some of them, but say for the 2835pro, it comes with a 1.2bar actuator, so i guess it'd be rated at 1.2bar.

[SLY33]

 

Also being that all of these turbos are rated at stock boost 10psi or so.So there will be room for more power.

These turbos arent rated at stock boost. From the HKS japan site, the HKS GT2530, 2535 and 2540 are rated at 1bar, and the GT2835ProS is rated at 1.2bar.

in regards to grepin running 1.6bar boost and toluene, wasnt that just during early runs? i thought he had a boost leak and got it sorted, ending up with somewher round 270rwkw at 1.3bar with no toluene?

trust33, im not sure why garret and hks equivalents arent the same, but im sure its been covered somewhere else.

[Roy]

Just because ppl call a high flowed VG30 turbo a 3040, mainly because it has a GT30 series cartridge, with a bigger "whatever" compressor, i dont think you are really comparing a real GT30 turbo.

Oz is great as we have so many places playing with turbos, i bet i can go to 3 places and get 3 different turbo combinations despite asking for the same setup, thats the downside of so many places doing their own things with turbos:(

And do you really make mpre power running an ext gate????? Perhaps you may get better boost control, perhaps, but surely it comes down to application, boost and power level, and A/R housing you are using more then whether its an internal gate?

[Nacho Vidal]

roy, so is the Garret GT3040 internal gate turbo previously mentioned, that UAS sell, not a real garret GT3040, but a highflowed VG30??

[Trust33]

:werd:

[mokompri]

im pretty sure you wont see much of a power difference by having the equivalent turbo in external gate configuration over internal... its just another way of bypassing exhaust gasses to control the speed of the compressor wheel, or boost in other words

only difference being that one bypasses it in the exhaust housing of the turbo, where as the other bypasses the gasses out of the manifold before it reaches the turbine, the power difference could only result from how the exhaust gasses are handled in the bypassing process.. whether its more efficient for gasses to bypass through the turbine housing or through an external wastegate is the question, and will of course depend alot i think on how the external wastegate pipe is integrated into the exh. manifold

[Roy]

roy, so is the Garret GT3040 internal gate turbo previously mentioned, that UAS sell, not a real garret GT3040, but a highflowed VG30??

Dont know about the UAS one, but i know from research just before i bought my turbo setup, there was no consistancy between what the various local turbo companies were offering, even though i was asking the same questions to all of them. But they all called them the same thing and claimed very different power levels.

3040 or not, i think B-man ran one of those UAS turbos for a pretty stout/punchy 250rwkws...so thats good damn power:)

[B-Man]

Yep - you are correct there Roy.

And now my HKS 3040 does 330 rwkw

And - it has just been totally reconditioned with new bearing and seals etc. Is back on the car now and will get a tune (again....) after having the HKS 2835 on it

Got to love the number of Turbos I have had on my car - and the number of ECUs.

Let's count them for fun :

Turbos : Stock, GCG Hi Flow, GCG 3040, HKS 3040, HKS 2835

ECUS: Stock, EMS Stinger, Microtech, Power FC

Now I want one of those Jim Berry clutches everyone keeps talking about

[Downforce]

Does anyone know if a HKS 2835R can be used with an external wastegate?

[Downforce]

Does anyone know if a HKS 2835 Pro S can be used with an external wastegate?

[Cubes]

Why would you want to do that GTTR34?

Buy the HKS2835S for cheaper if thats the case.

[Downforce]

Why would you want to do that GTTR34?

 

Buy the HKS2835S for cheaper if thats the case.

What's the price difference? I'm looking for info on the various HKS 2835 models and different options available.

[knore]

Yep - you are correct there Roy.

 

 And now my HKS 3040 does 330 rwkw

 

And - it has just been totally reconditioned with new bearing and seals etc. Is back on the car now and will get a tune (again....) after having the HKS 2835 on it

 

 Got to love the number of Turbos I have had on my car - and the number of ECUs.

 

 Let's count them for fun :

 

 Turbos : Stock, GCG Hi Flow, GCG 3040, HKS 3040, HKS 2835

 

 ECUS: Stock, EMS Stinger, Microtech, Power FC

 

Now I want one of those Jim Berry clutches everyone keeps talking about

 

 

Youve probably posted this already, but what mods did you have with the GCG hiflow and what power did it make?

[B-Man]

Max 240 rwkw. With Stinger, 550cc injectors, GTR cooler,