Hks 2535 On E85 Power?

[Joshbigt62r]

It's easy to make an HKS GT-RS look silly in every way, simply move away from the Garrett/HKS catalog and put an EFR6758 on there.

I didn't mean make a hks gtrs I meant make a gtx2867 with a cropped gt30 wheel instead of a gt28 turbine wheel. And discopotato was saying. The efr6758. Is there any dyno graphs of one on a rb25.

[Ryno]

Wow disco you have put way too much thought into this... But it's like you said early on, when do you ever get to hit the 300rwkw mark on the street? I certainly can't use my 265rwkw (or so) in first or second, so that leaves third and that's loss of license time. Sure it's cool to say you have 300rwkw, but that doesn't mean much in a daily drive when you can never use it.

Your reference about Heathcote Road made me smile, as my car is almost like an automatic now, in that I can just stay in 5th (if I choose) even when overtaking. There's tight corners on the way to work where I used to use third (to get the throttle response through the corner and out of it) but now I just use 4th. Torque rules!

Edited February 18, 2013 by Ryno

[Joshbigt62r]

What does the efr6758 retail for lithium? I have read a bit on these and they do look to be a good thing. I'd like to see a dyno graph if possible or your personal experience with them.

[Lithium]

I didn't mean make a hks gtrs I meant make a gtx2867 with a cropped gt30 wheel instead of a gt28 turbine wheel. And discopotato was saying. The efr6758. Is there any dyno graphs of one on a rb25.

Ahh yep gotcha.

And no, not like to find any RB25 results for them. You'd need a T25 manifold to fit an EFR6758 onto an RB25 - and really imho it is too small (I feel the same thing about GT2535 and GT-RS turbos as well) but it would spool like a maniac, and I'd say 300kw on E85 would be achievable.

I have not seen enough information on how well the trimmed GT30 turbine works, the GT2835 was a pretty popular choice so I assume it was pretty good - in the case of the GT2835/67mmGTX Frankenstein I am going to go tentatively with Discopotato on this one and say it could be a hell of a match up on an RB25. I'll roll with the idea that it is a little larger than the GT28 hotside I hate so much on RB25s, and the 67mm GTX compressor requires a reasonable amount higher shaft speed than the 71mm GT compressor to move the same amount of air which perhaps will work well in regards to the fact the turbine wheel will also spin faster....

I still prefer the idea of going a whole GT30 turbine, I like the way they drive and have in the past wondered if there are a bunch of GT30 cars which have been tuned averagely in the partial throttle areas or something as it comes across like everyone think they are dead at low rpms.

[GTScotT]

For the one asking about the cropped GT30 with GTX67 compressor, or anyone wanting to experiment with a cutprice HKS 2835 i do have an alternative...

Clicky:

http://www.precisionturbo.net/turbochargers/aftermarket-replacement/details/Aftermarket-Replacement-Turbocharger---5130/76

This is effectively a cropped GT30 turbo and a custom billet 71mm wheel. So its pretty darn close to a proper 2835, but with what PT consider to be an improved compressor. Definitely something I think an RB25 owner would want to try if looking for sub 300kw and bulk torque (on 98).

[Joshbigt62r]

And what rear housing would you run gtscottt? I guess you would have to pitch the t25 options and run a adaptor plate? Otherwise run a gate off the exhaust housing perhaps? So it's basically a cropped gtx3071. What are others thoughts on this? Does the precision turbo come surge slotted? I didn't see anything mentioning it but I could have missed it.

Cheers Josh

[GTScotT]

No surge slots, its a T04B style compressor housing by the looks of it. I wouldnt discount anything because of the no surge slots, nor would I compare it to a GTX3071...

Just consider it to be a reworked 2835. PT are saying it should spool better and make more power. So if you set your expectation to a reasonable result that a HKS 2835 would produce you shouldn't be disappointed. Remember that even if you bought an actual HKS 2835 it can still break your heart in terms of expecting the best, like any turbo. So don't aim for the maximum.

Depending on your intended setup you could use either the .63 or .82, dependant on your manifold and gate combo. If you were to use the money saved on the turbo itself (compares to a GTX or HKS) you could put the money towards a decent manifold and I would then run a .63 and a heavy gate. If limited to the stock manifold I would probably stick to the .82 to try and keep heat away. Bare in mind HKS ran the thing in .67 internal gate housings so a .63 on a high mount with a 50mm gate would probably be pretty awesome.

It should be said that a 2835 is actually laggier than a 3071 in terms of feel, but is more brutal in delivery. The GT30 wheel provides a more linear effect. You should expect roughly 270kw on 98, probably over 300 on E85 (up to 330 id say).

To my understanding, cropping the wheel has the following effect: 'laggier' but more brutal delivery (come on boost a little later but reach full boost quicker), more flow yet falls off quicker (more midrange power but lower peak figure). It could be said that the powerband will be stronger yet narrower, taller yet not as broad. That is my view anyway.

I hope this helps.

[discopotato03]

I can only guess what what the fictitious "GT2967R" would make but it should do better than a GTX2867R and spin up a bit sooner than the new GTX3067R - depending of course on T housing AR size .

Garretts claiming I think 500 hp from this GTX3067R and if you factor in Mirandas inside leg measurments and estimated the rest maybe 450 at the crank and guesses 390+ at the wheels . On the bleeding edge .

The nearest real world comparison would be a GT2835 Pro S run as hard as possible with E70/85 on a slightly polished RB25DET .

I know the drift world is all over the GTX2863R and GTX2867R but I don't see a mass migration to the GTX3067R , possibly because it would trade some low to mid torque for a bit more top end and that probably isn't as critical to drifters .

Could the "GTX2967R" shift the balance towards the slightly bigger cropped GT30 turbine , who knows . No one will till someone tries it . For Garrett to do it they'd need to see if theres enough meat in their castings to machine up ok with their slightly smaller turbine dimensions and then profile it for the cropped turbine . It should fit in with their goals of a compact unit making good grunt and help showcase their latest compressor technology .

Be a bit of an orphan but if it raised interest and had a catchy name maybe a win win for them .

A .

[Lithium]

What does the efr6758 retail for lithium? I have read a bit on these and they do look to be a good thing. I'd like to see a dyno graph if possible or your personal experience with them.

Oh yeah, they seem to go for around $1400USD - comparable with a GTX2867R.

[Chris32]

Hi guys, sorry to dig up an older thread

I've just got a 2535 for my car. Goal is quick street car, so needs response rather than all out top end, hence why I chose the 2535

Quick question - I can't find any info anywhere to tell me if a all in one split dump/front pipe will fit with the HKS exhaust housing, as they have the divider built in

Anyone running a similar dump pipe?

[Dose Pipe Sutututu]

use a bell mouth, split ones are gay...

I had a HKS2535 back in the days, not a bad turbo but you get really bored of it.

[Chris32]

use a bell mouth, split ones are gay...

I had a HKS2535 back in the days, not a bad turbo but you get really bored of it.

Will it fit however?

[Dose Pipe Sutututu]

Will it fit however?

Yes the rear housing is a 6 bolt Nissan style flange, unless you've got some weird one. I used a dim sim eBay special dump/down pipe from eBay and it fit up well enough.

[Chris32]

Ok cheers. Dunno what brand it is, as it was on the car when I bought it

[discopotato03]

I agree with Lithium on the "full" GT30 based turbos . The GT28 based ones of which the GTRS was probably best will make reasonable low to mid range torque but the exhaust flow isn't there . Cropped GT30 was a HKS tweener idea that in my opinion only ever worked in their turbine housings . Things like 2535 and GTRS will always be better than the standard ceramic Hitachi so if that's the ask then they have their place on very mild engines .

There probably isn't an ideal turbo that goes as close to bolting on as say a GT3076R (dimensionally) or a GTX3067R and the 2835 Pro S is effectively dead .

I think the thing most people really want is strong part throttle torque and RB25s lack what RB30s have by 500ccs and 500 revs . An RB25 is easily good enough at 3000 plus but some want more at part throttle between 2-3000 .

So without a capacity increase you have to compromise and sadly the conservative one means strangling the hot side . In a perfect world R33s would have had an RB30 and probably 3.9 or 3.7 rear gears . They would have been a nicer overall package I suppose like a VLT (torque wise) but with a better head and you'd think an SMIC and higher CR . I wonder how soft turbo wise they would have gone to get 206Kw from an RB30DET , probably the GTt turbo and intercooler and 4 pounds of boost .

I still haven't seen any 0.63AR IW GTX3067R results on an RB25 but in this day an age that's as conservative as I'd go with a new turbocharger . If you don't drive in slow traffic everyday then I think a 0.82 AR GT30 like a 76R or GTX71R is the go because they suit an RB25 from 25-2700 revs up if tuned properly preferably with modern injectors .

Personally I think R33 gearing is a tad short to be a relaxing cruiser but it had to be that way to get some go out of a nearly 1400 kilo car with a tiny ceramic turbine .

[R31 POWER]

Chris32, If the dump pipe has a divider that protrudes past the dump flange, it will hit the built in turbo one. Otherwise, what ever dump fits a stock turbo will fit yours.

Personally id hunt down the original spec dump that was available with the gt2535. Pics of it below.
http://www.sau.com.au/forums/topic/202920-hks-gt2530-dump-pipe-recommendations/

[Chris32]

This is what I have, well 99% sure without pulling it off to check inside.

Can anyone see any dramas using it?

[Blackkers]

looks okay I guess; hard to say. test fit the turbo to it and check the wastegate flap doesn't hit or get stuck. It's a common problem

[Chris32]

Yeah that's the plan

Being a daily I might pull the dump off and test it on the turbo first, rather than get half way through and have to go searching for something else

[Chris32]

It's funny how things work. Had a paver flick up and get smash into the dump pipe today, it's cracked the weld on the flange

Looks like it will be coming off for repair and a test fit