Rb26 Turbo Comparision Graph (from Latest Hpi Mag)

[R31Nismoid]

Ye, thats a much nicer t04z graph and how it should look.

What spec is the motor? Cams? etc etc etc

b0bb0, can you update the sticky dyno thread again?

I think you graph dropped off... either that or it was some other persons t04z graph

[Swiper the Fox]

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?

BOBBO...nice graph dude, thats more like it. I guess thats in RWD?

Ferni...thats 391 AWKW not RWKW...from memory it was tuned around 12-12.1

we made 404 AWKW a week before that on 28psi with Apexi boost controller...swapped to a blitz and made 391 with 4psi less boost (just goes to show what a good EBC can do)

[ferni]

Am i missing something, 627rwhp is about 470rwkw.................. thats nothing like Dirtgarages graph.....

Dirt: Ahhh ok so awkw guess that adds a few more on there, so yours makes really good power on 2530's... i guess still belivable tho...

How does the boost controller make more power? If the controller is doing its job and holding the set boost level, then it shouldn't matter what boost controller you are using 24psi with an apexi is the same as 24psi with a blitz... as long as its holding the boost....

(ps i use a blitz as well so not saying the apexi is better)

[shanef]

I think what he means is that the blitz ebc holds boost much better than the apexi. i had an apexi in my 33 and i found it wouldnt make the 'set' boost quickly and also it wouldnt hold it.

apparantly the blitz ebc's make boost as soon as it can, and holds it right to redline. and they are also cheper than the apexi's

[Sydneykid]

Is there some question about Paul’s power figure being accurate?

The ¼ mile time and TS indicates to me that it is pretty accurate.

As usual the answer is in the numbers;

From memory HKS rate the 2530’s at 320 bhp each

Most people accept that HKS underrate their turbos by around 10%

320 X 2 X 110% = 704 bhp

704 bhp = 525 kw – 80 kw losses = 445 4wkw

And that rating is using 100 ron fuel. Using something a little more oxygenated can give as much as 15% above that.

So I personally have no problem with the power figure

cheers .

PS, Paul’s car has ~50% more power at 4,000 rpm, that’s 2530 response.

[Swiper the Fox]

Am i missing something, 627rwhp is about 470rwkw.................. thats nothing like Dirtgarages graph.....

Dirt: Ahhh ok so awkw guess that adds a few more on there, so yours makes really good power on 2530's... i guess still belivable tho...

How does the boost controller make more power? If the controller is doing its job and holding the set boost level, then it shouldn't matter what boost controller you are using 24psi with an apexi is the same as 24psi with a blitz... as long as its holding the boost....

(ps i use a blitz as well so not saying the apexi is better)

The apexi struggled to hold the boost steady at high levels...anything over 25psi was a real battle for it. The Blitz ramped up to preset boost level quicker and held it steady as you can see from the printout. I have my hands on the apexi graph and will upload it later so you can see the difference.

[ferni]

The apexi struggled to hold the boost steady at high levels...anything over 25psi was a real battle for it. The Blitz ramped up to preset boost level quicker and held it steady as you can see from the printout. I have my hands on the apexi graph and will upload it later so you can see the difference.

Ahh i see but we were talking about peek power so how fast it ramps up has nothing to do with peak power... but yeah you can adjust the gain on the blitz to make it ramp up a bit quicker, i would of though the apexi could do the same thing, as for holding a steady boost line then i guess thats what makes it a better quality product

[B0BB0]

BOBBO...nice graph dude, thats more like it. I guess thats in RWD?

Just to clear up a few things, this is simon's dyno graph. R32 GTS on here. i also run a similar to4z setup but dont have any dyno sheets on my pc. i was just using it to show the similar responce to paul's setup.

The motor has forged internals, and hks 272 cams.

Am i missing something, 627rwhp is about 470rwkw.................. thats nothing like Dirtgarages graph.....

you can compare it to his race fuel graph, either way i wasnt talking about top end power, just the responce of the setup. which are very similar for both.

[B0BB0]

oh and yes it was rwd. they have a 4wd dyno down where i get my car tuned, so i will get a 4wd print out shortly.

[mazgtr]

Is there some question about Paul’s power figure being accurate?

Nope. I like most am amazed at DirtGarages results, clearly they have spent the time/research/testing required to achieve a power figure i didnt think possible from turbo's as small as 2530's. Their results are not in question.

R31Nismoid is right when he stated that the boost levels, fuel,tune, mods and results shown in the article arent clear and thus is not a 100% be all and end all comparison. But its good enough to at least gauge what the different turbo's look like. Its still gold for owners looking to upgrade.

DirtGarage, that dyno graph at 24PSI and pump fuel is more impressive to me than the 442KW C16 run. 391AWKW on CRD's dyno is massive figure. What time/MPH did the car run at this level?

Starts to make me think that my eventual goal of a 10sec pass might still be possible on my HKS 2540's.

That TO4Z graph is also very impressive. Instant 10sec GTR, and from what i know the turbo is very responsive for a large single.

Cheers.

[Gav]

oh and yes it was rwd. they have a 4wd dyno down where i get my car tuned, so i will get a 4wd print out shortly.

Actually BOBBO is being a bit coy here.

The tuning shop where he works has a very interesting graph overlaying most of the terbs described here fitted to GT-Rs. I think he's also been in most of them (I know I have).

My thoughts for what they're worth:

I have GT-RS terbs fitted to a well built RB28 (HKS kit) with big cams and head work. Click for dyno graph

Having driven an almost identically specced RB27 (JUN kit) with 25/30s, I can certainly vouch that this car has a bunch more torque lower in the rev range and sacrifices very little top end to me (I reckon I'll have 30 more peak hp max).

Also, having been in 2 TO4Z GT-Rs with standard cranks, again these sacrifice little low down torque but have an absolute phenomenal top end to boot!

So whilst I would dearly love to defend my investment in the GT-RS terbs, I can honestly say that for most of the GT-R owners that are looking to upgrade terbs, BOBBO's advice is spot on:

• 25/30s
  
• TO4Z
  

BOBBO see if you can get the dyno graphs as an overlay as discussed!

[mazgtr]

So if the HKS 2530's are considered the best low-mount setup, and the T04Z the best large single, when it comes to power/response. Whats considered the best high-mount twin setup?

With all these people fitting T04Z's, what am i looking at price wise to upgrade to this setup? I allready have the supporting mods, engine/fuel/ic/ecu.

Haveing HKS dumps and front pipes, would i need to change my exhaust aswell?

[R31Nismoid]

the turbo itself... manifold and dump pipes/associated plumbing for AFM (if ur still using them)

Changeover, selling old gear vs new.. probably not as bad as you would think

[Swiper the Fox]

DirtGarage, that dyno graph at 24PSI and pump fuel is more impressive to me than the 442KW C16 run. 391AWKW on CRD's dyno is massive figure. What time/MPH did the car run at this level?

11.2 was the best ET using STD road tyres and STD gearbox unsure of the MPH mid to high 120's would be about right. This was my first outing in the car (Stacey was driving it before this meet) and im sure a 10sec pass would have been possible with more practice. Stacey used to race the car with about 330-340 kw and ran flat 12's, not bad eh. We are strapping her back in the car now as she wants a 10 sec pass to her name.

[rb26s13]

hell yer

[mazgtr]

Might have to put a TO4Z or 2530 combo on the to-do list...

Edited June 15, 2006 by mazgtr

[mazgtr]

11.2 was the best ET using STD road tyres and STD gearbox unsure of the MPH mid to high 120's would be about right. This was my first outing in the car (Stacey was driving it before this meet) and im sure a 10sec pass would have been possible with more practice. Stacey used to race the car with about 330-340 kw and ran flat 12's, not bad eh. We are strapping her back in the car now as she wants a 10 sec pass to her name.

Wow. It seems that the 2530's are able to generate great times by being able to record great 60foot times. This must be where their added response over 2540's and the like make it quicker over the strip, even if MPH trap speeds are similar. On your 10.38 run i noticed your 60foot was 1.51sec!!! Thats insane!!!

I think my 2540's would drop off boost/revs too much between gearchanges to enable a 10sec pass.

Ill drop by CRD this week and chat to Jim, they built my car for the previous owner a couple of years ago.

Cheers.

ps good luck Stacey in joining the 10sec club...

[B0BB0]

BOBBO see if you can get the dyno graphs as an overlay as discussed!

if i will remember i will get the graph, of 2530's vs gt-rs vs to4z vs twin to4z vs gt42. haha however they are all on different motors.

[Swiper the Fox]

Wow. It seems that the 2530's are able to generate great times by being able to record great 60foot times. This must be where their added response over 2540's and the like make it quicker over the strip, even if MPH trap speeds are similar. On your 10.38 run i noticed your 60foot was 1.51sec!!! Thats insane!!!

I think my 2540's would drop off boost/revs too much between gearchanges to enable a 10sec pass.

Ill drop by CRD this week and chat to Jim, they built my car for the previous owner a couple of years ago.

Cheers.

ps good luck Stacey in joining the 10sec club...

My best was a 10.36 with a 1.490 60' im no expert drag racer either so with a dog box and a better driver it would have done 9's

[9krpm]

It's very interesting to see how this thread has progressed

Like most people have agreed, I believe that these dyno runs are as close as a comparison you can get in life. The only better comparision is if this is all done in one car but no one has that much money+time to burn for such R&D.

I think any other dyno result adding to this thread will just cloud the discussion. There are just to many other variables such as tuners' tuning style, fuel, dyno, dyno correction etc etc for a reliable comparison. Sorry but no disrespect intended here.

For clarification, the T5187Z refers to T517Z with 8cm housing. The car has big top end hks cams, 2.6L and FC D jetro. The result was obtained at 19psi and on pump fuel. All cars were tuned by Martin Donnon.

I think from the first graph you can say that the t517z performs well. It is compariable to the t04z at top end (in the reliable rev range) and would not differ to the GTRS much if the car has stock cams. I know the owner of the car with the t517z well and have been in the car a few times. It just smoke street tyres in first gear on launch or looses traction at all 4 wheels at around 8krpm (in first gear).....that's probably why busky felt the "power dip" at top end Boost starts at 3krpm and full boost is achieved at around 4.6krpm. A littl e bit laggy for some but all you need is bleep the throttle a few times and dump the clutch The car is a daily driver built for drag and track work. The owner did 1:20 at Mallala and 1:18 with Luke Youlden behind the wheel at Mallala. The car weights around 1530kg. It hasn't had a chance to see the drag strip yet....but when time permits it will be interesting to see what it can do with sticky rubbers.

As far as I know it has been running strong since the beginning of this year. Great tuning Mr Martin Donnon!

Edited June 15, 2006 by 9krpm