Rb26 Turbo Comparision Graph (from Latest Hpi Mag)

[paulr33]

could you honestly have more than twin gt-rs's worth of street power?

on a 26/30 i would have thought they would have been spot on for max power and quick wind up (well the quickest possible for massive power)

are the gtrs's ball bearing or plain bearing?

i recall the twin 2530's are plain bearing

[Beer Baron]

2530s are ball bearing. GT-RS ae also ball bearing.

[CruiseLiner]

could you honestly have more than twin gt-rs's worth of street power?

on a 26/30 i would have thought they would have been spot on for max power and quick wind up (well the quickest possible for massive power)

are the gtrs's ball bearing or plain bearing?

i recall the twin 2530's are plain bearing

im 99.9% sure they are both ballbearing, as with all the hks turbos (recent ones anyway)

[paulr33]

let me see if i can find where i read it

i know the single gtst versions are ball beariing

for some reason ive read the twins arent

[wrxhoon]

Both ball bearing, GTRS'S are newer turbos, bothe turbs about the same lag.

[paulr33]

ok anyone with twin 2530s

do you have a restrictor on the oil feed

http://www.skylinesaustralia.com/forums/in...pic=93332&st=20

that thread seems to be very helpful

it seems to indicate if you have a restrictor then they are ball bearing

[CruiseLiner]

strangely enough my hks t04z needs a restrictor but my mates BB garrett gt30/40 doesnt need one, any reason y????

Edited June 8, 2006 by CruiseLiner

[paulr33]

i think im loosing this one

[paulr33]

found it (post #96)

http://www.skylinesaustralia.com/forums/in...ic=72151&st=80#

[paulr33]

maybe there are two versions of the 2530's in twin format

this page seems to indicate they come with restrictor bolts http://forums.freshalloy.com/showthread.php?t=148813

which would indicate they are ball bearing

[shanef]

the gtrs's are only rated to 440hp each (+/-10hp, cant remember exactly) and that only equates to 880hp at the flywheel, when they are set up to the max, with the most boost they can run, i presume somewhere in the high 20's. taking out the 20% drivetrain loss, for rwd, this would only give me 704rwhp, not the 700awhp i was looking for. so i'd need a twin set-up rated at roughly 500hp each, and want all of your opinions on which turbos would be the most responsive.

reason for responsiveness required is this car is going to be set-up for track work, but sitll be driven on the street for cruises etc.

could you honestly have more than twin gt-rs's worth of street power?

on a 26/30 i would have thought they would have been spot on for max power and quick wind up (well the quickest possible for massive power)

are the gtrs's ball bearing or plain bearing?

i recall the twin 2530's are plain bearing

[r33_racer]

for track work having that much power i would think you would be creating quite possibly a slower car then what you could have. For that sort of power you would have alot of top end, i believe that much power would make your car slower, whether its from wheel spin, or boost drop off during gear changes. I think v8 super cars are nearing 700bhp, and you want 700awhp! Most quick circuit cars are generally around 650bhp max i believe. My opinion is that a fast circuit car is built around excellent midrange power with good top end, but it depends on what track your running as to how usable that power will be to you.

[R31Nismoid]

strangely enough my hks t04z needs a restrictor but my mates BB garrett gt30/40 doesnt need one, any reason y????

They all have an internal restrictor Brad.

On the cartridge itself that you cant see unless you pull it all apart.

Interesting you need a restrictor at all

[fatz]

twin high mount 2835 would give ya that extra kick in the guts

but form my experience on a 2.6 litre gtr motor twin 2835's dont hit full boost till 6k rpm

but on a 3.1 litre im thinking 4k rpm

[R31Nismoid]

been in a gts-t with twin 2835R's/RB26 years ago

absolute insanity

[nfi]

My guess is the trust turbos on the dyno graph are 518z with the 0.72 rear housing. I am not sure whether that is the 8cm or 10cm (or neither) which is how trust measure the rear housing but that would be my guess.

Maybe someone could convert the 8cm and 10cm to a/r.

[mazgtr]

the gtrs's are only rated to 440hp each (+/-10hp, cant remember exactly) and that only equates to 880hp at the flywheel,

this would only give me 704rwhp, not the 700awhp i was looking for. so i'd need a twin set-up rated at roughly 500hp each, and want all of your opinions on which turbos would be the most responsive.

reason for responsiveness required is this car is going to be set-up for track work, but sitll be driven on the street for cruises etc.

Mate 700AWHP and responsive track GTR are at complete odds with each other.

Like a few boys have said, for a quick track car, masses of topend power doesnt make it quicker around a track. Mid range torque and responsiveness makes it quick. A really quick track GTR usually selects turbo's for the midrange, 700AWHP is enough to run a low 10sec quartermile, possibley a high 9sec pass with suspension and transmission work. Not many 9sec GTRs are quick around a track or on the street mate.

For the best street GTR, with a bit of track work id suggest the HKS GT-SS twins. 300-330 AWKW.

But if your building up a bigger engined GTR, theres no point going with turbo's this small.

2530's would also IMO be to small for your application.

2540's can produce up to 400AWKW, and GTR Jason on this forum has clocked some amazing track times around some Sydney circuits with them. But their getting a bit old now, and have since been replaced by the GTRS's. Looking at that dyno graph id say these turbo's would be great for your application. You could get 600-700 AWHP outta them, and they're more responsive than a T04Z.

GTR's are the biggest/powerfull low mount turbo's you can fit.

After them, your looking at a large single like the T04Z or a small high mount kit, like the Trust TD05 twin setup. TD06's would be to laggy for track work IMO.

Personally i think you need to rethink your power goal and your intended use for your GTR. Becasue at the moment i think they're at loggerheads. You'll find that a 550-600 GTR with GT-SS's will more than likely be quicker around a track than a laggy 750BHP monster.

[Gav]

Mate 700AWHP and responsive track GTR are at complete odds with each other.

Like a few boys have said, for a quick track car, masses of topend power doesnt make it quicker around a track. Mid range torque and responsiveness makes it quick. A really quick track GTR usually selects turbo's for the midrange, 700AWHP is enough to run a low 10sec quartermile, possibley a high 9sec pass with suspension and transmission work. Not many 9sec GTRs are quick around a track or on the street mate.

For the best street GTR, with a bit of track work id suggest the HKS GT-SS twins. 300-330 AWKW.

But if your building up a bigger engined GTR, theres no point going with turbo's this small.

2530's would also IMO be to small for your application.

2540's can produce up to 400AWKW, and GTR Jason on this forum has clocked some amazing track times around some Sydney circuits with them. But their getting a bit old now, and have since been replaced by the GTRS's. Looking at that dyno graph id say these turbo's would be great for your application. You could get 600-700 AWHP outta them, and they're more responsive than a T04Z.

GTR's are the biggest/powerfull low mount turbo's you can fit.

After them, your looking at a large single like the T04Z or a small high mount kit, like the Trust TD05 twin setup. TD06's would be to laggy for track work IMO.

Personally i think you need to rethink your power goal and your intended use for your GTR. Becasue at the moment i think they're at loggerheads. You'll find that a 550-600 GTR with GT-SS's will more than likely be quicker around a track than a laggy 750BHP monster.

Good advice. I've got a lot of hardware installed along with my GT-RS terbs. I'm changing the inlet cam to a longer duration 272 item, but I really doubt I'll crack the 600 rwhp level. I think 570 to 570 rwhp is a more realistic maximum for these terbs.

[shanef]

Good advice. I've got a lot of hardware installed along with my GT-RS terbs. I'm changing the inlet cam to a longer duration 272 item, but I really doubt I'll crack the 600 rwhp level. I think 570 to 570 rwhp is a more realistic maximum for these terbs.

But are you using a 3ltr engine? Not sure if i did metion it or not, but my engine consist's of an rb26 head with rb30 bottom end

I think i'll just be happy with what the gtrs's produce and see what time i can get around qld raceway in...but then again the power mite not be enough n i may strive for more...as it always happens

[R31Nismoid]

Mate 700AWHP and responsive track GTR are at complete odds with each other.

You could get 600-700 AWHP outta them, and they're more responsive than a T04Z.

GTR's are the biggest/powerfull low mount turbo's you can fit.

If you basing the GT-RS vs T04Z on the graph comparo here... im not too sure.

Im still un-convinced by one dyno graph comparo with unknown spec'd motors.

Its too hard to make a call without the detail of every car used, and the subsequent modifications.

the gtrs's are only rated to 440hp each (+/-10hp, cant remember exactly) and that only equates to 880hp at the flywheel, ... 704rwhp, not the 700awhp i was looking for.

As you said, give you 704rwhp... thats 704awhp

So i dont see how it isnt what you are looking for.