400rwkws From Gt3540 .82

[Lithium]

In regards to the Japanese Performance R33 GTS25t - I'd love to be reminded the 1/4mile time and ET of BU5TER which has a T51R on an RB30 hybrid.... I have a magazine article here saying it ran 10.5 @ 130mph withn 441rwkw!? Am I missing something? Thats running a drag-setup auto and I'd say with 3l it will have a torquier power delivery, and Dyno Dynamics dynos read a lot lower than a particularly high reading hub dyno. How come there aren't BS claims flying around about that time with that car?

I remember the Wild 1 Motorsports guy on here claiming big power figures from a GT3540R on their R33 and ended up doing a 10 USING NOS on their one.... and that didn't go as quick as Jap Performance either, despite the huge kick the NO2 would give it. Anyway, I know of a few cars doing 10s on pump gas with GT3540Rs - a mate of mine did a 10.7 with his EVO in full street trim (including tires) using .82a/r. Consider the .82a/r a turbo capable of getting you near 130mph on your average Japanese car on pump gas.

Edited February 4, 2007 by Lithium

[N I B]

This RB25-30 combo has GT35 with .63housing because responce for drifting is its goal.

24PSI and modest tune for long life.When it was runninb 420rwhp it ran 134mph on Sava cheapo tyres.

When this car goes to the drag next we will try a harder tune but for now its close to what you want.

Lag is no ones freind.

[kastin]

cheers thats awsome,

so the 505hp is at flywheel?

[N I B]

Rear wheel. It really should be in a GTR because its got totally Zero traction.It went to the track last friday for its first drift practice but at much lower boost till the drivers upto speed.

[Cubes]

This RB25-30 combo has GT35 with .63housing because responce for drifting is its goal.

24PSI and modest tune for long life.When it was runninb 420rwhp it ran 134mph on Sava cheapo tyres.

When this car goes to the drag next we will try a harder tune but for now its close to what you want.

Lag is no ones freind.

NIB... Compared to others running cams it more so resembles the 1.06 spool/torque I've seen on various rb25/30 setups.

Your 100% thats a .63? It comes on almost like a .82 with stock cams. From what I've seen. You don't have a boost curve sheet handy?

EDIT: But in saying that it is making ~250rwkw around 4200rpm which with a .82 would require in the 20+psi range. Interesting. 250rwkw at ~4000rpm. No wonder it shreds tyres.

[N I B]

Im sure on the Turbo cause its had 3 different Turbs to find the best match.

[Cubes]

Nice..

So care to share how much boost you were running?

[N I B]

Its in the post with the graph just above.

[Cubes]

opps...

[BU5TER]

In regards to the Japanese Performance R33 GTS25t - I'd love to be reminded the 1/4mile time and ET of BU5TER which has a T51R on an RB30 hybrid.... I have a magazine article here saying it ran 10.5 @ 130mph withn 441rwkw!? Am I missing something? Thats running a drag-setup auto and I'd say with 3l it will have a torquier power delivery, and Dyno Dynamics dynos read a lot lower than a particularly high reading hub dyno. How come there aren't BS claims flying around about that time with that car?

Because if you done your homework you'd know I ran the 10.5 at 20psi with pump fuel, 235 radial tyres with a 1.8 60ft at 20psi I was making around 400rwkw also an auto car will always be a bit down on mph compared to the manual

hope that helps

[DennisRB30]

Food for thought on the front cover 0.5 VS 0.7 Everyone just seems to ignore the front cover and only worry about the turbine housing.

Check this out. The smaller front may actually be better for average power.

http://www.fordxr6turbo.com/forum/index.php?showtopic=32271

According to Garrett, the smaller front cover has a very minimal effect on power, and smaller AR's are actually better for higher boost levels. So I think I am on a winner with the 0.5 front. I was going to change it but I am not now. I think it might be better!

Compressor A/R - Compressor performance is comparatively insensitive to changes in A/R. Larger A/R housings are sometimes used to optimize performance of low boost applications, and smaller A/R are used for high boost applications. However, as this influence of A/R on compressor performance is minor, there are not A/R options available for compressor housings.

http://www.turbobygarrett.com/turbobygarre...bo_tech102.html

Edited February 5, 2007 by DennisRB30

[2rismo]

I'd love to be reminded the 1/4mile time and ET of BU5TER which has a T51R on an RB30 hybrid.... I have a magazine article here saying it ran 10.5 @ 130mph withn 441rwkw!? Am I missing something? Thats running a drag-setup auto and I'd say with 3l it will have a torquier power delivery, and Dyno Dynamics dynos read a lot lower than a particularly high reading hub dyno. How come there aren't BS claims flying around about that time with that car?

Because unlike your good self, most people know what conditions this time was run under. I have photos of the smoke pouring off of the small, radial tyres even at the moderate 20psi boost level used for these passes. Are you missing something? Probably not. Just keep in mind that magazines tend to talk about the best power a car has made and the best ET/TS a car has run HOWEVER these two figures may not go hand in hand at the time.

I remember the Wild 1 Motorsports guy on here claiming big power figures from a GT3540R on their R33 and ended up doing a 10 USING NOS on their one.... and that didn't go as quick as Jap Performance either, despite the huge kick the NO2 would give it.

The car setup was atrocious for this power level. Although the run was made on slicks it was made with the factory manual transmission and was a handful to drive. Mechanical problems made a run with the Powerglide impossible at the time. When did he use the nitrous (N2O btw)? How much power did it make when it ran? You have no idea.

Anyway, I know of a few cars doing 10s on pump gas with GT3540Rs - a mate of mine did a 10.7 with his EVO in full street trim (including tires) using .82a/r. Consider the .82a/r a turbo capable of getting you near 130mph on your average Japanese car on pump gas.

How on earth does a 2-litre 4-cylinder apply to this discussion????

[N I B]

I think you can say now that yes you can make the power you want.

[S3_Girl]

Not a Rb, but on a 2j ,with everything stock bar 272 cams, my mates

3540 .82 made 410rwkw on a dd dyno on pump fuel on 23-24psi.

This was maxed out with no increase if more boost was added.

So i would think around 400-410 rwkw is it 3540 .82 wise.

It ran 10.8 at 128mph in a 1600kg Mk.3 supra when it made 370rwkw. So

i think the dyno reads about right.

cheers

darren

[Sydneykid]

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

[cameron]

You goto be spot on their SK,

Our R33 RB25 ran the GT3540 0.82A/R at 32psi of boost, hks 256cams with 8.8 lift no porting of the head, ran out of fuel to make extra power up top needed another 044.

On 98octane it came out with 370rwkws and a 11.0 @ 129mph on slicks.

So to answer the theads question...

I think on race fuel and a bit of head porting you would see 400rwkws.

But you would still have to run up around the 30psi area.

So I would say it is safer to go the bigger exhaust housing.

[kastin]

Sydneykid

are you replying to the main question or are you just talking about the jap performance r33?

Cameron do you know what CR he was running?

There are alot of conflicting reports..

[cameron]

Sydneykid

are you replying to the main question or are you just talking about the jap performance r33?

Cameron do you know what CR he was running?

There are alot of conflicting reports..

The engine had Arias piston and a 1.8mm tomei headgasket - Im unsure of the CR but if you know what comp the arias piston you could proberly work it out, Im guess somewere between 7.5:1 - 8.2:1 very low for a RB25, but this allowed us to run a consistant 32psi with out stressing the engine too much.

[discopotato03]

Dennis RB30 , thats a rather simplistic overview of the comparitive differences in alterations of Area Radius Ratio with turbine and compressor housings .

Yes changing turbine housing A/R makes a greater overall difference because this is what attempts to regulate the turbos rotating assembly speed in relation to engine speed .

Changing compressor housing A/R will alter the choke flow capacity of the compressor in relation to pressure ratio meaning maximum useful airflow flow vs boost pressure . This is how its possible to gain a bit more maximum compressor capacity and optimise it around the desired boost pressure to a degree .

It was explained to me years ago that the larger housing has less resistance to gas flow so moves a lot of gas at lowish pressure . The smaller housing has more resistance to flow so needs greater pressure to move the volume .

The thing to remember is that generating higher pressure means the turbine has to work harder so this will affect exhaust gas speed and turbine inlet pressure . Its all inter related so changes in one area will make the engine see a different world on both inlet and exhaust sides pressure wise .

Cheers A .

[DennisRB30]

Dennis RB30 , thats a rather simplistic overview of the comparitive differences in alterations of Area Radius Ratio with turbine and compressor housings .

Yeah, fairly oversimplified, however I was only talking about comp AR's not rear housings. But I also linked to a real world example of a comp cover change on the XR6 site where the smaller cover seems to be much better over all than the larger one (well on an XR6 anyway). I don't know why the Garrett site only had that one small paragraph on comp covers when the site goes into a lot of technical detail in other areas.

Seems most of the RB30DET guys are getting a lot more lag with 0.82 rears than I am with a 1.06 rear and 0.5 front. I get 15psi by 3500rpm in second gear with a $200 ebay manifold (auto) probably equal to 3rd gear with a manual. According to the XR6 thread I linked to, the smaller front gives a LOT more response. Most people just ignore the front cover, or just get the biggest one possible when that may not be the best option. I'm just trying to get people to take notice of the front cover as it may have a bigger effect of the power curve than what they are led to believe.

From XR6 site. Chart is 0.5 front VS 0.7 front. As you can see it has MUCH better mid range power with some power loss in the top end, however it was running 2 psi less in the top end, and they reckon once they up the boost to where it was with the 0.7 it will "cream" the 0.7 there too. This is only one comparison and its on a 4 litre engine, but its enough to make you think twice about comp cover selection.

Low down saw an improvement of ~55RWKW and 105Nm of Torque at a lowly ~3650rpm - Massive Improvement and only upping boost by ~3psi.

Up top at best saw a 10RWKW loss to the .70 cover, but the .50 is down ~2psi up there.. If we can get boost up in the rev range, it should cream the .70 - and my clutch which, btw is still stock and 70,oookm old

Edited February 5, 2007 by DennisRB30