Rb26 Turbo Comparision Graph (from Latest Hpi Mag)

[rb26s13]

yes that dyno sheet shows 2530's being absolutely awesome setup for low mounts

[DoughBoy]

To me a GTR running a 10sec pass with a big single on pump fuel is more impressive than a "drag" GTR running 9sec passes.

Check out Bu5ter then- pump fuel, 20psi, 235 tyres... RWD and mid 10's to boot.

[rb26s13]

doughboy you forgot to mention

rb26/30

3speed jatco with massive stall (5500 or 6000 or something like that)

the 235 tyres are mickey thompsons and i was under the impression they were 255/50/16's?

and the t51r kai..

bit different to a 2.6 running 2530's with little poncams.. and the power there pulling is very similar

[discopotato03]

Mazgtr , no the RB26 specific GT-SS's don't use the high performance GT28 turbine like the SR20 GT-SS does . In fact the 2510 and the RB26 GT-SS are probably the only Nissan specific GT25/28 HKS BB turbos that don't . When looking for specs check the turbine trim number , if it says 76T its most likely the good one . 2540's will always be laggy because even with the good GT28 turbine its still a 54mm turbine trying to drive a 76mm TO4E compressor . In todays terminology it would be a GT2876R but with a E series compressor rather than a 76mm GT37 wheel .

[DoughBoy]

doughboy you forgot to mention

rb26/30

3speed jatco with massive stall (5500 or 6000 or something like that)

the 235 tyres are mickey thompsons and i was under the impression they were 255/50/16's?

and the t51r kai..

bit different to a 2.6 running 2530's with little poncams.. and the power there pulling is very similar

Hahah goose

[rb26s13]

goose?

[DoughBoy]

Yeah goose, I merely showed an example of a single turbo RB running on pump that has done a 10 second pass. Maybe it would have been better to mention UREADY-R32 GTR who did a 10.8 with a plain bearing T04R, stock gearbox and a similar built engine to toogle - forged pistons and 264 cams.

I deliberately didn't want to post more since this is a thread about a magazine article showing turbos on a stock motor running low boost on pump fuel, not about stripped out race cars running huge boost on race fuel that generated obscene power levels out of small oversped turbos that disintegrated after less than 5,000k's. Another good example of "stock" motors putting out power is that one in the states in a full chassis car, completely internally stock motor with every bolt on under the sun that did ~900rwhp.

Apples for donuts that case may be, but it's already in the thread.

[rb26s13]

i was under the impression the dyno sheet comparo in the magazine were unknown spec engines.. meh who knows

[Swiper the Fox]

not about stripped out race cars running huge boost on race fuel that generated obscene power levels out of small oversped turbos that disintegrated after less than 5,000k's.

I very much hope that comment was not directed at our car....if so its misinformed dribble.

a few facts....

...................the turbo's were fine until the rear oil feed became blocked (after speaking to a few people in the industry this is quite a common cause because of the design of the factory lines and why its nearly always the rear turbo to fail).

...................on inspection it was found the other turbo to be perfectly healthy and in serviceable condition

....................the turbo's were also second hand when i purchased them and probably did in excess of 40 000klm's before failure.

.....................1475kg plus 100kg (1575kg total) driver is by no means a light weight race car...20kg lighter than stock.

.....................only two compnents in the engine were not factory Nissan...the pistons (which add no performance value only reliability) and cams.

.....................the power levels and performance of the car was quite repeatable at both dyno and track events.

.....................huge boost was only ever used for dyno comps. 27-28 psi was used at the track and is within the efficiency range of HKS turbo's.

If people don't have the balls or the knowledge to push their cars to their full potential mate it ain't my problem.

Edited June 14, 2006 by DiRTgarage

[rb26s13]

well said dirt garage

[Swiper the Fox]

well said dirt garage

Yeah sorry for the rant........... but people who think they know what's going on, and what is actually going on, are sometimes very far removed.

Just had a think about it and those little 2530's were great...they have been on three different engines...Paul Thomas' car, our car with stock engine and our car with the freshened up engine with forgies...they have a place close to my heart, served me well and anyone who tries to knock them is a fool....

[SCOOP]

Yeah sorry for the rant........... but people who think they know what's going on, and what is actually going on, are sometimes very far removed.

Just had a think about it and those little 2530's were great...they have been on three different engines...Paul Thomas' car, our car with stock engine and our car with the freshened up engine with forgies...they have a place close to my heart, served me well and anyone who tries to knock them is a fool....

I can say that this is true, Definatly used on three different engine's. All did its fair share of work!

[DoughBoy]

Ahh you don't get it. This thread was about a turbo comparison using the same dyno/spec motor/fuel to illustrate the differences in the setups. Sure there might be a few issues as to the validity of the results but at the end of the day it was as close to direct comparisons as they could get.

Throwing in your 2530 dyno graph using different fuel at a boost level you just claimed you never drive the car at is pointless. Where is the relevance to the Wilall tests? Of course it's going to smash it, hell even at 18psi it would have more area under the curve due to the ridiculous amounts of timing thrown into it. The turbos would come on a hell of a lot earlier and have a massive advantage.

Regarding your old setup, I even said it to you on the phone a few days ago that it was pretty damn good. "Normal" people would just upsize the turbo than keep going back with tuning and different fuels, but you ended up getting good results from bolt on replacements. I could go on about it but that's not the purpose of this thread.

[mazgtr]

I agree. The turbo comparison in the article is a basic guide to the results produced by the different turbo combinations on said GTR.

The boost level used and the fuel they were run on is 99% sure to be street friendly.

Quite simply NO street useable turbo setup/tune, wether new or old is going to come anywhere near to the results achieved by TWO-06L in terms of power and response. But thats not a fair comparison.

Most GTR owners are not going to spend the time/money/research/labour/testing required to enable turbo's as small as 2530's to achieve similar results, and even then its not a practical street setup IMO, requireing obscene boost levels for the street, and leaning on the engine to the extent that "street useable/reliable" is hardly a fair description, and the fact your always only one bad batch of pump fuel or one really hot day away from disaster.

Dirt Garages dyno sheet is simply going to wipe the floor with anything else you can post up to compare with. But i think their results with this combination is the exception rather than the rule. As far as i know only 1 other GTR in Oz has run a 10sec pass on low mount turbo's, and it needed C16 to enable the 2.0Bar running through its 2540's to achieve it, after being expertly setup by CRD.

So it would seem that the new HKS GT-Rs are now the best option for those wanting maximum power from a low-mount setup thats street friendly. Although their response is laggier than 2530's, their topend power advantage while running on pump fuel and reliable boost levels gives them the edge IMO if power and quick drag strip times/higher MPH results are your desired goal.

2530's are great turbo's, no doubt. With near stock boost response, while adding 60-70KW at the wheels running street useable boost levels is very impressive. This gives you a GTR that can power around a race track, tear up the street and run 11sec passes at the strip.

A great "allround" setup. But, if a repeatable/reliable 350+AWKW is your goal, 10sec passes or 130MPH trap speeds in a streetable setup is what your after, then the 2530's are not a viable street option, as the boost levels required to achieve this rule out the use of pump fuel, the very thing that makes a car "streetable".

How the new HKS GT-Rs would go at 2.0Bar and C16 is yet to be seen, but is not really relevent to 99% of owners. The vast majority of owners want a safe/reliable/repeatable setup that runs on pump fuel and is is at home on the street. Transporting your GTR on a flatbed to the workshop everytime you want a retune to enable 2.0Bar to be used grows tiresome. Not forgetting the fact that as soon as Avgas/C16 is used the car is not longer legally able to be driven on the road, and thus is no longer a "street GTR" anyway. Takeing this into account the new HKS GT-Rs offer the best "bang for your buck" from a low mount setup for a genuine street GTR.

Cheers,

Interesting opinions. Lets keep it friendly though boys..

Edited June 14, 2006 by mazgtr

[rb26s13]

i think i'll probaly end up goin the 2530 low mounts.. how ever.. im not a gtr.. but i know dirt garage's results were on race fuel n all that.. but hell.. someone post up a dyno sheet of 2530's being push to there limits on pump fuel than compare them to magazine comparision.. would be very very interesting to see

[Yawn]

Very interesting read guys. Just wanna clarify and hear other ppls opinions on the Garrett GT2560R? From what i have been told they are comparable to the HKS 2530? Anyone know how these 2 compare? From what i know they are roughly the 2530s equivalent but with the capability to have slightly more top end with almost stock response? Anyone using the 2560s got anything to add to this discussion?

Cheers

[R31Nismoid]

I agree. The turbo comparison in the article is a basic guide to the results produced by the different turbo combinations on said GTR.

The boost level used and the fuel they were run on is 99% sure to be street friendly.

Thats the core problem.

Its not different combinations on the SAME GTR, its different graphs, from different motors.

Unless each motor has its mods itemised out under the graph is essentially useless for comparisoon as it gives you no accurate data to work from.

You cant be 99% sure, how can you be? Do you know the spec of each motor? No-one has been able to provide this yet, maybe you know something we all dont?

[Swiper the Fox]

Thats the core problem.

Its not different combinations on the SAME GTR, its different graphs, from different motors.

Unless each motor has its mods itemised out under the graph is essentially useless for comparisoon as it gives you no accurate data to work from.

You cant be 99% sure, how can you be? Do you know the spec of each motor? No-one has been able to provide this yet, maybe you know something we all dont?

this ones for you Wazz (rb26s13)

ok guys...24psi and pump fuel

Edited June 15, 2006 by DiRTgarage

[ferni]

that seems a bit more like it... 390rwkw, turn off shootout mode and that will drop it to around 360-370rwkw which is in line with other good 2530 setups... what kind of AFR's go with that graph?

[B0BB0]

i would think this setup matches the efforts of dirtgarage. Garret TO4z

this is pump fuel also. and about 24psi if my memory serves me correct.

i think at the end of the day to4z or 2530's are the go.