400rwkws From Gt3540 .82

[Lithium]

Obviously everyone has noticed that it is a DynaPack dyno, hub style therefore no wheels and tyres, no wheelspin and no rollers. Hence higher numbers, all things being equal. It should realy be expressed as rhkw (rear hub kilowatts) not rwkw (rear wheel kilowatts) as there are no "wheels" on the car when it made that power run.

The 128 mph indicates around 360 rwkw.

Based on past experiences, it is set to kW SAE which if I remember rightly means "at the engine" on a DynaPack. So the 450 kw less say 80 kw for losses = 370 rwkw in our usual terminolgy (Dyno Dynamics)

Summary;

ET = 345 rwkw

TS = 360 rwkw

Corrected dyno = 370 rwkw (in Dyno Dynamics speak)

Let's split the difference and say 365 rwkw, does that sound better?

cheers

Thanks SK. As far as I understand SAE isn't an at the engine correction, but it is a standardised adjustment which ultimately results in high readings. It has already been said earlier in this thread that the dyno it ran on reads high though, which is why the fact that it ran a 10.6 @ 128mph was mentioned in the first place - to give a more realistic idea of what a .82a/r GT3540R would do. Shame there are so many angry people on here who want to call BS about everything without using the soft stuff in their skull a little more.

The car was running ~21psi, and was on BP Ultimate (98) when it did the runs. It has a thicker headgasket, a tubular high mount exhaust manifold, custom plenum, the biggest dump pipe they could fit (can't remember if 3.5" or 4" even). The reason I'd mentioned 4cyl GT3540R times/traps in here is the trap speeds are always going to a be rough indicator of the power the thing is making with the turbo, and it was running on pump gas - seeing as there is so much obvious contention about dyno results.

I could have mentioned that someone in NZ has managed an 8.9 running a GT3540R on an RB30/25 hybrid, but the rest of the package is so far different from anything here the 4cyl results would have been MUCH more comparable.

[Cubes]

Dennis.

I know a bloke running an xr6t turbo on his rb30det. That makes 15psi by 3900rpm BUT its running on the stock exhaust manifold. I have noticed the smaller comp cover appears to bring the power on a little more linear as it begins making boost early and then slowly increases boost over a wide rpm; compared to the .7 comp cover it makes say 5psi by 3000rpm then another 500rpm its making 20odd. So the .7 feels a little more nothing then everything. This is seat of the pants as I've been in and driven both.

I also know of 2 others with the usual GT35r .7 comp and .82 rear that make what ever boost they throw at it just over 3500rpm still on the stock exhaust manifold.

All though the 400rpm difference doesn't sound alot the BIGGEST difference between the 1.06 and .82 is that the .82's go much harder and lag a hell of a lot less in the lower gears. In the top 3rd+ gears, they feel almost the same.

What diff gears are you running? The examples above were running 4.3's. Most likely part of the problem with the larger 1.06 a/r.

It would be quite interesting how your xr6t turbo would go with a .82 arse end.

[DennisRB30]

Dennis.

I know a bloke running an xr6t turbo on his rb30det. That makes 15psi by 3900rpm BUT its running on the stock exhaust manifold. I have noticed the smaller comp cover appears to bring the power on a little more linear as it begins making boost early and then slowly increases boost over a wide rpm; compared to the .7 comp cover it makes say 5psi by 3000rpm then another 500rpm its making 20odd. So the .7 feels a little more nothing then everything. This is seat of the pants as I've been in and driven both.

I also know of 2 others with the usual GT35r .7 comp and .82 rear that make what ever boost they throw at it just over 3500rpm still on the stock exhaust manifold.

All though the 400rpm difference doesn't sound alot the BIGGEST difference between the 1.06 and .82 is that the .82's go much harder and lag a hell of a lot less in the lower gears. In the top 3rd+ gears, they feel almost the same.

What diff gears are you running? The examples above were running 4.3's. Most likely part of the problem with the larger 1.06 a/r.

It would be quite interesting how your xr6t turbo would go with a .82 arse end.

I run an Auto with 4.1 gears. I actually changed them from 3.7. First gear still fries the tires. So it does NOT have the lag problem from low speeds you are talking about. So I would be silly to bother with a 0.82.

Also your findings on the 0.5 building boost more gradually seems to oppose the dyno chart I provided where the 0.5 comes on much harder and the owner says its more of a tire fryer with the 0.5.

Edited February 7, 2007 by DennisRB30

[Cubes]

I run an Auto with 4.1 gears. I actually changed them from 3.7. First gear still fries the tires. So it does NOT have the lag problem from low speeds you are talking about. So I would be silly to bother with a 0.82.

Ahh the auto.

Its amazing how much of a difference they make to spool and drivability of a large turbo.

Another mate (dangerman4) runs a GT35r .82 on his Rb25, that makes all its boost by 4200rpm (24psi) and 5psi by 3000rpm. That fry's first, second and third and doesn't have that feeling of first gear flicking so quick the turbo hasn't had time to spin up.

Also your findings on the 0.5 building boost more gradually seems to oppose the dyno chart I provided where the 0.5 comes on much harder and the owner says its more of a tire fryer with the 0.5.

By 3600rpm odd boost is well and truley in.

I should have been a little more clear..

I am talking about the boost build rpm area, when there is no boost to some boost, up to say 5psi.

After that first 5 or so psi boost increases much quicker

So the .5... You will start to see boost slightly earlier than the .7, this is what I mean by the more linear feel. The progression on to boost.

The xr6 dyno sheet doesn't read low enough to tell.

For the xr6 you would have to run it from almost idle. Remember they are making good boost at 2000rpm so that dyno sheet is useless for what I am describing.

I guess you could describe it as the windmill effect disco has talked about in the past.

Hard to describe but definitely noticable by the seat of the pants.

[discopotato03]

I guess the choice of compressor housing comes back to how much power and power delivery as Cubes says how it climbs onto boost . I can see pros and cons of large turbine housing/small compressor housing and medium turbine housing/large compressor housing .

The XR6 spec GT3582R I think was attempting to have low backpressure and smooth power (torque) delivery (for Mr/Mrs/Miss) so used the TO4E .50 comp A/R housing . Pure guesswork but its possible that having reasonably low turbine inlet pressure and a compressor/housing combination that started pumping at lowish engine revs (for 4L) gave them an acceptable load balance of exhaust to boost pressure . I don't remember the exact figures but I think N/A to turbo XR6 power figures were around what 190 and 240 Kw with the turbo version having better average torque . To do this it needs to have positive inlet manifold pressure from a bit above idle to feel good but at relatively low boost pressure so that its not too snakey . The low manifold pressure and an intercooler would help them to have a reasonable CR and not be too detonation prone in hot weather . This stuff is beginning to make me think about GT3076R's and comp housing A/R's but thats for another string .

There is another compressor housing that can fit the GT3582R cartridge and it has found its way onto a few XR6T's , Brett reckons its a bolt up alternative for the XR6's TO4E sized backplate from memory and is supposed to be .70 A/R ratio but with the TO4E's sized inlet and outlet . Off the top of my head I think non port shrouded "E" housings are 2.75" inlet and 2" outlet so it must have a slightly smaller internal passage than the TO4S .70 A/R housing . To be smaller means higher air speed for the same compressor rpm so something a bit fishy here . Very wild guess but it may possibly be a .70 A/R TO4E housing factory profiled for the GT3582R's 56T 82mm GT40 compressor . It may prove to be the in between of more "linear" power delivery vs how much do you want and in over a fairly narrow engine speed range .

It'd be real interesting to see all three compressor maps wouldn't it ?

Cheers A .

[dangerman4]

I guess the choice of compressor housing comes back to how much power and power delivery as Cubes says how it climbs onto boost . I can see pros and cons of large turbine housing/small compressor housing and medium turbine housing/large compressor housing .

The XR6 spec GT3582R I think was attempting to have low backpressure and smooth power (torque) delivery (for Mr/Mrs/Miss) so used the TO4E .50 comp A/R housing . Pure guesswork but its possible that having reasonably low turbine inlet pressure and a compressor/housing combination that started pumping at lowish engine revs (for 4L) gave them an acceptable load balance of exhaust to boost pressure . I don't remember the exact figures but I think N/A to turbo XR6 power figures were around what 190 and 240 Kw with the turbo version having better average torque . To do this it needs to have positive inlet manifold pressure from a bit above idle to feel good but at relatively low boost pressure so that its not too snakey . The low manifold pressure and an intercooler would help them to have a reasonable CR and not be too detonation prone in hot weather . This stuff is beginning to make me think about GT3076R's and comp housing A/R's but thats for another string .

There is another compressor housing that can fit the GT3582R cartridge and it has found its way onto a few XR6T's , Brett reckons its a bolt up alternative for the XR6's TO4E sized backplate from memory and is supposed to be .70 A/R ratio but with the TO4E's sized inlet and outlet . Off the top of my head I think non port shrouded "E" housings are 2.75" inlet and 2" outlet so it must have a slightly smaller internal passage than the TO4S .70 A/R housing . To be smaller means higher air speed for the same compressor rpm so something a bit fishy here . Very wild guess but it may possibly be a .70 A/R TO4E housing factory profiled for the GT3582R's 56T 82mm GT40 compressor . It may prove to be the in between of more "linear" power delivery vs how much do you want and in over a fairly narrow engine speed range .

It'd be real interesting to see all three compressor maps wouldn't it ?

Cheers A .

Hi guys

you mentioned a while ago you may have found some port shrouded gt3582r-iw .7 comp covers!

are you still able to get your hands on them?

Cheers..

Darren

Hey Joel

you didnt make it on the BSM cruise? i was hoping to take you for a spin again..

[Cubes]

BSM Cruise?

Bugger.

[600hp]

Hypertune's B16A use to make 365kw at the wheels with one of GCG 35/66spl units on 24 psi.

so i'm thinking that it should not be that hard to make over 400 on a normal GT35R with the 1.06.

[85URK]

still even so if the guy made those hp figures in the japanese motorsports car ( or what ever it is) how long would it last, 1 2 runs before bang time....??

u can only put so much boost in before it goes kaput!

[discopotato03]

That picture of the port shrouded compressor housing I posted a while back was from the US . I have seen pics of drilled ones as well though I'm not sure how well they work . The interesting one was HKS's TO4Z snout cartridge and it would not be to dificult to do it that way with a bit of machine work . Possibly even easier would be to get the .70 TO4S housing machined with an end milling cutter to form the jellybean shaped ports and slot the inside with a thin parting off style cutting tool .

As usual , comes back to money and what services are available to you .

Cheers A .

Edited February 7, 2007 by discopotato03

[AndrewD]

Thanks SK. As far as I understand SAE isn't an at the engine correction, but it is a standardised adjustment which ultimately results in high readings. It has already been said earlier in this thread that the dyno it ran on reads high though, which is why the fact that it ran a 10.6 @ 128mph was mentioned in the first place - to give a more realistic idea of what a .82a/r GT3540R would do. Shame there are so many angry people on here who want to call BS about everything without using the soft stuff in their skull a little more.

The car was running ~21psi, and was on BP Ultimate (98) when it did the runs. It has a thicker headgasket, a tubular high mount exhaust manifold, custom plenum, the biggest dump pipe they could fit (can't remember if 3.5" or 4" even). The reason I'd mentioned 4cyl GT3540R times/traps in here is the trap speeds are always going to a be rough indicator of the power the thing is making with the turbo, and it was running on pump gas - seeing as there is so much obvious contention about dyno results.

I could have mentioned that someone in NZ has managed an 8.9 running a GT3540R on an RB30/25 hybrid, but the rest of the package is so far different from anything here the 4cyl results would have been MUCH more comparable.

Lithium,

I dont think you should take SydneyKid's not "at the engine" correction as a generalised comment.

SAE or ISO or any other standard correction is to correct for atmospheric variances and nomilize scores for comparison.

[1JZ.747]

Obviously everyone has noticed that it is a DynaPack dyno, hub style therefore no wheels and tyres, no wheelspin and no rollers. Hence higher numbers, all things being equal. It should realy be expressed as rhkw (rear hub kilowatts) not rwkw (rear wheel kilowatts) as there are no "wheels" on the car when it made that power run.

That it makes it max power at over 7,500 rpm, using a 0.82 to 1 A/R turbine is amazing, more like a miracle. More info needed...

It has Jun 260 degree cams, but they have 9.3 mm lift. Any comparison with the more common 8.X lift cams (eg; Tomei Poncams) is meaningless.

It also obviously has head work, otherwise it wouldn't make power at that high rpm. (Yep, the spec list says it does).

So removing restrictions (cams and head work) means similar airflow at lower boost level. Maybe 19 psi isn't so wide of the mark

The 10.65 for the 1/4 indicates no excess of traction, considering the mph. Nismo suspension, so I am not surprised. Around 345 rwkw would give you that sort of time.

The 128 mph indicates around 360 rwkw.

Based on past experiences, it is set to kW SAE which if I remember rightly means "at the engine" on a DynaPack. So the 450 kw less say 80 kw for losses = 370 rwkw in our usual terminolgy (Dyno Dynamics)

Summary;

ET = 345 rwkw

TS = 360 rwkw

Corrected dyno = 370 rwkw (in Dyno Dynamics speak)

Let's split the difference and say 365 rwkw, does that sound better?

cheers

spot on the numbers SK

MPH tells no lies

[2rismo]

MPH tells no lies

Quoted for truth.

[Lithium]

Quoted for truth.

Hard not to roll ones eyes at some of these comments.... but yeah, the trap speed tells no lies which is why the time and trap was mentioned in the first place. Just a shame you guys seem to treat any result from a dyno which reads different to your precious Dyno Dynamics with contempt.

AndrewD - Yeah, thats why I said that SAE is a standardised adjustment. The number which comes out the other end often comes out higher than if DIN adjustment was used on a hub dyno.

Edited February 9, 2007 by Lithium

[GT3584R]

That picture of the port shrouded compressor housing I posted a while back was from the US . I have seen pics of drilled ones as well though I'm not sure how well they work . The interesting one was HKS's TO4Z snout cartridge and it would not be to dificult to do it that way with a bit of machine work . Possibly even easier would be to get the .70 TO4S housing machined with an end milling cutter to form the jellybean shaped ports and slot the inside with a thin parting off style cutting tool .

As usual , comes back to money and what services are available to you .

Cheers A .

MTQ Brisbane do the 'hole' style ones for 3082/3582's on exchange basis or to your cover

I have one on my GT3584R with a T04E 0.5 cover (off the GT3071R) got rid of nearly every bit of compressor surge that was there under acceleration, work very well and sound awesome too with the induction whistle they get !!!

Edited July 14, 2008 by GT3584R

[discopotato03]

There are a few variations on the port shrouding theme and you'll have to excuse me but there are versions that may not work so well .

I think you can take it for granted that Garrett ones work though they do give off the shrill jet turbine like whine .

The HKS funnel piece like they fitted to their GT3037S turbos may shut them up a bit and would be quite easy to make .

The way I see it if a machinist could bore out the snout of a T04S comp cover he could probably turn up a bell mouthed insert and come up with a way of bolting or staking it in place . The critical bit is where the slot is in relation to the outer tips of the half height or splitter blades . Precission Turbo or PTE in the US seem to make a workable system and use that cover on what they call their HTA35R .

ATM I'm not a big fan of the drilled covers because I think they look better than they work - to some .

If you can see how HKS did their T04Z comp housings insert you'd see how it differs from merely drilling holes in a housing and slotting the inside of the snout . I just keep wondering if the simple method has problems with air entering drilled holes and making the right hand turn to exit the front of the housings snout . Also removing the burrs in this area would be interesting .

Food for thought , cheers A .

[dangerman4]

Ahh the auto.

Its amazing how much of a difference they make to spool and drivability of a large turbo.

Another mate (dangerman4) runs a GT35r .82 on his Rb25, that makes all its boost by 4200rpm (24psi) and 5psi by 3000rpm. That fry's first, second and third and doesn't have that feeling of first gear flicking so quick the turbo hasn't had time to spin up.

By 3600rpm odd boost is well and truley in.

i should mention that the other day heading up willunga hill i flicked the auto into snow mode and then kept it in overdrive as low as i could without it kicking back into third. i managed to get 4 - 5 psi by 2400 rpm.

now as this is a constant revs wouldnt a manual do the same thing?

sorry for the OT but im around the 325rwkw at 24psi on a built auto rb25 running gt3582r-iw .82

Edited July 14, 2008 by dangerman4

[GeeTR]

DECEIVE has made 400rwkw with a .82 and cams in a 26 @ 1.6(?) bar hasn't he?

Edited July 14, 2008 by GeeTR

[FineLine]

MTQ Brisbane do the 'hole' style ones for 3082/3582's on exchange basis or to your cover

I have one on my GT3584R with a T04E 0.5 cover (off the GT3071R) got rid of nearly every bit of compressor surge that was there under acceleration, work very well and sound awesome too with the induction whistle they get !!!

I opted for this option and I dont regret it. apart from the funky jet turbine whistle it did bring boost on a cuppla hundred earlier.

[Lithium]

I opted for this option and I dont regret it. apart from the funky jet turbine whistle it did bring boost on a cuppla hundred earlier.

What the drilled holes in the compressor cover? If anything, it will make it a bit laggier...